3.2.1 Creating, Opening and Saving Project Groups and Templates

New: creates a new project group (TPG) with no projects defined.

Open > Project Group: opens an existing TPG file. The Select TREAT Project Group screen will appear. The Select TREAT Project Group screen allows the user to see the description of the project group and the list of project names included in each TPG file. If another TPG file is active at that time, the user will be presented with a dialog with three options. Option one: opens the newly selected TPG and saves the currently open TPG with all changes. Option two: opens the newly selected TPG without saving any changes made to the currently open TPG since the last Project Groups > Save operation. Option three: cancels the process of opening a new TPG, keeping the active TPG in the same state as before initiating the Open operation.

Open > Edit Template: opens a PGT (Project Group Template) file. This works the same way as opening a TPG (TREAT Project Group) file, as described above, except that only Project Group Template (PGT) will be visible in the Select a Template screen.

Open Most Recent: opens the last TPG file that the user has worked with on this computer.

Recent Groups: this sub-menu contains up to eight TPG file names, representing the eight most recent TPG files opened on this computer. The first file in the list is the most recently opened one.

Save: allows storing all changes to the current TPG group (not only the selected project within the TPG) to the TPG file. When working with TPG the actual work is done over a temporary copy of the TPG. This approach protects the original file from any corruption and data loss. Frequent use of Save while working on a project will significantly decrease the risk of lost data from system crashes. To decrease probability of data loss, TREAT prepares a temporary backup copy of the file before updating the original TPG file with the latest changes. The backup copy of the file is only temporary and exists only for the time period between starting and completing the Save operation. Save works the same way for PGT (Project Group Template) files as it does for TPG (TREAT Project Group) files.

Example

The original TPG file name is Group1.TPG. After user chooses to save the TPG, TREAT creates a backup copy of the file called ~Group1.TPG. This backup copy is deleted only after saving the TPG file is successfully completed.

If the active TPG was created using the Project Group > New menu item then Save and Save As have the same behavior, asking the user to enter a file name and description for the TPG.

Save As > Project Group: saves changes to the currently active project group under a new name as a TPG file. After the TPG is saved under the new name, it becomes the currently active TPG (opened in TREAT). No changes have been saved to the original TPG file since the last Project Group > Save operation.

If the active TPG was created as new, then Save and Save As have the same behavior, asking the user to enter a file name and description for the TPG.

If you want to create a back-up copy of the TPG file, you can either copy it using Windows Explorer or save it under a new name using Save As feature.

By default the TPG files are saved to the Taitem Engineering\TREAT\Project Groups folder. If TREAT is installed in the default folder, then the full path is C:\Program Files\Taitem Engineering\TREAT\Project Groups.

A warning is shown if the entered file name duplicates an existing file name because saving will overwrite an existing file with the same name.

Save As > Template: saves changes to the currently active project group under a new name as a PGT (Project Group Template) file. This works the same way as saving as a TPG (TREAT Project Group) file, as described above. Files saved as Project Group Template files (PGT) will be visible in the Select a Template screen, but not in the Open Project Group screen.

Edit Description: presents the user with a screen to enter a description and/or any notes for the project group that is being saved. The description is shown on Select TREAT Project Group screen and is useful for the record keeping and easy file identification.

3.2.2 Store Editable Libraries

Store Editable Libraries: presents the user with questions to determine which editable libraries from the currently active TPG should be stored to internal library depository for use with the other TPG files.

The following editable libraries may be selected: Contractor, Customer, Daily Weather Data, User and Utility Rates.

The depository can store only one copy of each library for future copying to other projects.

The Store Editable Libraries option is enabled when a TPG is opened. No changes are made to the libraries in the open project when the Store Editable Libraries option is used. If an editable library, for example Customer Library, is stored then that Customer Library from this TPG will be included in each TPG that is loaded from this point on if user selects to update editable libraries on the window opened from Project Group > Options (see below).

3.2.3 Preferences

The Preferences tool serves the following purposes.

1. It allows the user to customize many of TREAT’s defaults. For example, the user can set custom heating and cooling season dates to be used for every newly created project instead of standard TREAT dates.
2. It allows the user to automatically fill in the inputs that are likely the same for every project. For example, the user can define fuels to be automatically generated for every new project at the time the project is created, eliminating the need to fill in the TREAT Fuels/Rates screen. The user can also specify a long-term and daily weather site to be used for each new project. A wide range of other inputs can be set through Preferences.
3. It allows the user to specify lighting and appliances to be generated at the time a new space is created. This feature is useful for users who do not collect lighting and appliance information on site. Automatic generation of lighting and appliances saves time and allows the user to account for interaction between base load and heating/cooling.
4. Preferences data is used to supply inputs for several other tools such as New Building Wizard, Visual Inspection Wizard and Measurements Wizard. See description of these tools for more details.
5. It helps to speed up inputs on Surfaces and Windows screen by specifying the list of typical constructions to be shown in the Description combo boxes. This often eliminates the need to look for the surface in TREAT libraries.

All project inputs generated by Preferences can be modified later using regular TREAT screens, just as any other inputs.

TREAT comes with a default set of preferences. You may customize these defaults by modifying and saving input on Preferences screens.

Select Preferences from the Project Group menu to open the Preferences screen.

Fuel/Rates tab: Up to four fuels can be selected. They will be automatically included in each project and will be available for selection as heating or hot water fuel in the New Building Wizard.

Weather/Defaults tab: Weather sites, heat and cooling seasons, and other inputs that appear on the Weather/Defaults input screen can be selected to be automatically included in each new project.

Surface Constructions tab: Up to 20 frequently used surfaces from the Surfaces Library can be selected. They will appear in the drop-down lists on the Surfaces screen, Surface Insulation Improvement Wizard, and New Building Wizard. One surface can be selected to appear at the top of the list; the rest of the list will be sorted according to the sort order selected.

Windows tab: Up to five frequently used glazings and frames can be selected. They will appear in the drop-down lists on the Windows screen, Window Replacement Improvement Wizard, and New Building Wizard. One of each can be selected to appear at the top of the lists.

Lighting/Appliances tab: There are seven sub-tabs for different types of spaces. The types of spaces correspond to the selections on the TREAT Spaces screen. For each type of space, there is an option to automatically add lighting or appliances when the space is created. For each type of space, lighting inputs of Typical Watts per Fixture, Hours On/Day and Average Wh/SqFt-Day can be specified. For each type of space, up to 10 appliances can be selected from the Appliance Library.

Inspections tab: Up to 10 inspections can be selected to be included in the Inspections Wizard. The Inspections Wizard is accessible from the Inspections screen and quickly creates inspection records of the types specified.

Measurements tab: Up to 10 measurements can be selected to be included in the Measurements Wizard. The Measurements Wizard is accessible from the Measurements screen and quickly creates measurement records of the types specified.

Reset to Default button: This will clear all preferences that the user has selected and restore the default preferences that are included with TREAT.

Next button: This scrolls through the tabs on the Preferences screen.

Save and Close button: This saves changes and closes the screen.

Cancel and Close button: This closes the screen but does not save any changes made since the last time the screen was opened.

3.2.4 Options

Options: This opens a screen that has two tabs.

General tab allows a user to select whether the Model Inspector will be shown each time calculations are completed. The Model Inspector may also be started by clicking Tools > Model Inspector on the main menu.

Library Updates tab allows a user to change the pre-defined settings for updating TREAT libraries. The default settings are shown below:

The default settings are recommended.

Non-Editable Libraries should be updated to take advantage of the new appliances, surfaces, etc. that are added to the libraries periodically.

Inputs in the Editable Libraries area allow selecting editable libraries, which should be replaced with the library from the central depository when a TPG file is opened. This functionality should be used with caution, because it allows overwriting the libraries stored in the existing TPG file with new ones, which may cause data consistency problems.

Tip: After you import daily weather data in a TPG, you may want to update the libraries for other TPG files with the latest weather data. This may be done as follows:

1. Select Project Group > Store Editable Libraries menu option and click OK to Daily Weather Library upgrade. The Daily Weather Library will be stored to the central library depository.
2. Open Project Groups > Options window. In the Editable Libraries area select Prompt to Upgrade Libraries and select Daily Weather Data checkbox.
3. Click Save to save the new inputs and close the window.
4. After that, each time you open a TPG you will be asked if you want to upgrade the editable libraries. If you answer Yes, then all the editable libraries that were checked in the window described in Step 2 will be replaced with the versions of these libraries stored in the internal library depository.

Warning

Use caution when upgrading editable libraries, especially the Contractor, Customer and User libraries, to prevent data loss or inconsistency in project data. For example, you may have a project in ProjectGroup1.tpg that has customer John Smith, who is customer #3 in the Customer library. While working on ProjectGroup2.tpg, you choose to store its Customer library to the internal library depository. In that version of the library, customer #3 is Tom Brown. If you replace the Customer library in ProjectGroup1 with the Customer library from ProjectGroup2 using the TREAT library upgrade feature, then all projects in ProjectGroup1 that referenced John Smith will now have Tom Brown as a customer. Information for John Smith will be lost.

Close TREAT: will save any modifications to the open project, then save the TPG and close TREAT. By default Close will try to save the active TPG (including any possible changes), which will overwrite the original TPG file. A dialog screen with three options will be presented to the user allowing canceling the closing operation, saving the active TPG file or closing TREAT without saving the active TPG. If TREAT is closed without saving the TPG, then the file corresponding to the active TPG file will contain only changes done before the last Project Group > Save operation.

6.5.1 Spaces

The building can be modeled either as a single space or multiple spaces. The decision as to whether multiple spaces are necessary depends on many factors. If two spaces are operated at different temperatures (have different thermostat set points, overheated or under-heated due to distribution loss, imbalance or internal gains), different heating or cooling schedule, have different mechanical ventilation loads, or one space (perhaps an attic, basement or garage) is unconditioned, then use of multiple spaces may be necessary. If you plan to use TREAT for sizing a heating or cooling system, then each area for which the design load is of interest should be modeled as a separate space. A little experimentation will soon reveal the cases in which a more complex multi-space description is needed. If each room in the building is modeled as a separate space, the input may be very time consuming. In most single-family houses all rooms that belong to one heating/cooling zone and are serviced by one thermostat may be modeled as a single space.

1. If an unheated space is vented (for example if this is a vented crawl space) you may choose not to model it as a separate unconditioned space. Instead you may enter the surfaces that are adjacent to this space (floor of the first level) as adjacent to exterior.
2. An un-vented roof cavity that will be filled with insulation may be modeled as unconditioned space.

Space Type sets the defaults for all other input fields on this screen except for floor area. It also defines the occupancy schedule used by TREAT to calculate internal heat gains and default infiltration of unheated spaces.

Space Name allows the user to assign a custom name to the space. Be as descriptive as possible, because this name will be used on many screens to define the location of walls, lighting, appliances, etc. The space name must be unique for the project.

Ceiling height is the height of the ceiling in feet. If the space has a varying ceiling height (sloped ceiling) enter the average height for that space. Ceiling height is used in infiltration calculations to calculate building volume.

Floor Area – area of the space in square feet. For each space the product of the ceiling height and floor area should be equal to the actual volume of the space. Floor area is used to calculate defaults for the distribution system and in many reports that display area-normalized outputs.

Elevation is the height of the space floor above the floor of the lowest level. For example if the building has a basement then elevation of a space is equal to the height of the floor of this space above the basement floor. Basement elevation is equal to zero. The elevation is used to calculate stack effect.

Set the value of the Conditioned field to Yes if the space is part of the conditioned area (if it is heated and/or cooled).

Enter the average number of hours per day that the space is occupied in the Occupied field.

Persons is the number of people that are typically in this space when it is occupied. TREAT accounts for internal gains in calculations of heating and cooling annual energy consumption by generating hourly occupancy schedule based on number of persons, hours occupied and space type. The following logic was used:

1. Sleeping Quarters: center hours on 2 am.
2. Living Space: first 10 hours - center on 8 pm; next 8 hours center on 11 am; last 6 hours will be distributed between 12 am and 6 am as follows: start from 1 am, next 6 am, next 2 am, then 5 am, then 3 am, then 4 am.
3. Office : center hours on 1 pm.
4. All other spaces: half is centered on 7 am; the other half centered on 7 pm.

For heating load sizing, no credit is given for internal heat gains from occupants; however, occupancy affects cooling load sizing.

The Advanced button brings up a window with optional inputs for the selected space.

Is the space furnished box allows accounting for the thermal mass of furniture and light interior partitions. By default, the value is set to Yes for conditioned spaces and to No for unconditioned spaces. For spaces created in the versions prior to TREAT 2.5, the default value is No for all types of spaces.

Heavy (brick) interior walls allows accounting for the added thermal mass of heavy interior walls, such as a central fire place. The heavy walls may play an important role in solar gain calculations.

Use natural ventilation for free cooling during non-heating months allows modeling the effect of opening the windows when the outdoor temperature is below 68F and the space temperature is above 70F. Natural ventilation is modeled only for the months that are not part of the heating season, which is specified on the Weather/Defaults screen. Natural ventilation will not be modeled if a 12-month heating season is specified.

6.5.2 Walls/Surfaces

Energy modeling requires that each space have at least one wall/surface. In order for the model to be accurate you should enter all surfaces through which a significant amount of heat is gained or lost. Conditioned spaces may have surfaces adjacent to Outdoors, Ground or unconditioned spaces defined on Spaces/Rooms screen. Unconditioned spaces may have surfaces adjacent to Outdoors and Ground. No surfaces between conditioned rooms (interior partitions) may be entered.

Data input on the screen starts with selection the space for which the surface is being entered. Choose any space that you described on the Spaces/Rooms screen from the Surfaces In drop down box. Click the Next and Previous buttons to switch between spaces. The buttons are disabled if there is only a single space in the project.

1. Before leaving the screen use Next and Previous buttons to go through all the spaces in the project and make sure that at least one surface is entered for each space.
2. You do not have to enter each physical surface in the space separately. For example, for the basement you may choose to enter all four below-grade walls as a single surface, since exposure is not relevant. In this case use basement perimeter instead of wall length.

The Description field allows the user to specify the surface construction. You can either select constructions from the list of typical constructions or from TREAT Surface Library. The list of typical constructions in the combo box may be customized by editing Surface Constructions tab of Preferences that are accessible from Project Group menu. Select
keyword at the end of the list to open TREAT Surface Library.

Hold the cursor over the description input in the Input Area to view the complete wall description. The R-value in the description is the overall thermal resistance of the surface including framing and excluding air film.

The Code field is filled out automatically after the surface construction is selected. It can be used as a shortcut to enter surface descriptions without opening the library. When you start entering a new surface you may go directly to this field and enter the code. Surface construction will be displayed as soon as you move to the next field.

The Adjacent To field can be set to Outdoors and Ground or, if the surface is in conditioned space, it may also be adjacent to any unconditioned space that you have entered on Spaces screen.

The Exposure field must be filled in for all exterior surfaces except for horizontal ones (surfaces with zero tilt). Set exposure to NA for such surfaces.

Length and Height inputs define dimensions of the wall for heat loss and infiltration calculations. For horizontal surfaces such as floors and ceilings use Height field to enter width. The product of length and height must be equal to the gross surface area. TREAT will use door and window areas entered on the following screens to calculate the net surface area.

Use the Advanced Inputs button to edit surface name, tilt, elevation, overhang and side fins.

Name is an optional input that can be used to further describe a surface.

Elevation is the height of the bottom edge of the surface above space floor. It is used to calculate stack effect. Elevation of the floor is 0. Elevation of the ceiling is equal to the ceiling height. Elevation of a typical wall that goes from floor to ceiling is 0.

Tilt is the angle of the surface from horizontal in degrees. Enter 90 for a vertical wall, 0 for floors and horizontal ceilings and any number in between for a sloped ceiling.

Overhang and Side Fin Depth is used for exterior walls to model the effect of solar gain on energy consumption. TREAT assumes that the overhang is located at the top of the wall at a right angle to the wall. Left and right side fins are located at the corresponding edge of the wall at the right angel to the wall.

TREAT uses the following logic for modeling surfaces adjacent to ground:

Walls

• TREAT attaches 0.68′ layer of soil to walls that are 1ft high or less. Temperature of surrounding soil is assumed to be equal to the ambient air temperature for the hour.
• TREAT attaches layer of soil equal to WallHeight × 0.77 to walls that are between 1 and 3 feet high. Soil temperature is assumed to be equal to the ambient air temperature for the hour.
• Below grade walls that are more than 3 feet high are modeled as two separate walls. First wall is 3′ high, has 2.31′ layer of soil attached to it, and looses heat to ambient air temperature, Second wall is (WallHeight-3) feet high and has 3′ layer of soil attached to it. Temperature of surrounding soil is assumed to be equal to average annual air temperature.

Slab On Grade

Slabs are modeled as two separate surfaces. First surface is 3′ wide slab perimeter ring. It has 3′ layer of soil attached to it. Temperature of surrounding soil is assumed to be equal to the ambient air temperature. The second surface is of the same area as the remaining section of the slab and has 3′ layer of soil attached to it. The temperature of surrounding soil is assumed to be equal to the average annual air temperature.

Slab Below Grade

Losses are calculated from 3′ perimeter ring around the slab. 9′ layer of soil is attached to the perimeter wring and the temperature of surrounding soil is assumed to be equal to average annual air temperature.

Layers of soil are attached to the surface in order to model insulating properties of soil. Thickness of the soil layer is selected to approximate the length of heat flow path through ground. For the typical building configurations the algorithm produces results that are very close to heat loss coefficients specified in ASHRAE Fundamentals starts on page 8 of pdf which is page 2 the of the document.

6.5.3 Exterior Doors

Select the name of the space and exterior wall to which the door belongs from the drop down boxes at the top of the screen.

Use the Previous Space and Next Space buttons to switch between spaces in the project.

Use the Previous Wall and Next Wall buttons to switch between exterior surfaces of the selected space.

Click on the Wall Description field to display the default door construction, double-click to open the Door Library.

Use the Code field as a shortcut to enter a door description.

Enter Width and Height of the door in feet. These fields are used by TREAT to calculate the net door area. An Error message will be displayed if the door area is greater than the area of the wall to which it belongs.

Use the Quantity field to enter multiple doors of the same construction that belong to the same surface.

6.5.4 Windows

Select the name of the space and exterior wall to which the window belongs before entering data in the Input Line.

You can either select Glazing Description from the list of typical glazings or from TREAT Glazing Library. The list of typical glazings may be customized by editing Glazing Description on Windows tab of Preferences. Preferences are accessible from Project Group menu. Select
keyword at the end of the list to open TREAT Glazing Library.

Glazing Code is a numeric code that may be entered to specify the glazing without opening the Glazing Library.

Frame Description contains the specification of the window frame. Clicking on the field displays the default frame entered on Weather/Defaults screen. Double click on the field to bring up the Frame Library.

Select Frame Description from the list of typical frames shown in the combo box or from TREAT Glazing Library. The list of typical frames in the list may be customized by editing Frame Description on Windows tab of Preferences. Preferences are accessible from Project Group menu.

Select keyword at the end of the list to open TREAT Frame Library.

Frame Code is a numeric code that may be entered to specify the frame without opening the Frame Library.

The combination of Frame and Glazing allows the user to define a wide range of windows.

The NFRC (National Fenestration Rating Counsel) has a standardized testing procedure that is used to create the ratings for U-value and SHGC (Solar Heat Gain Coefficient) that appear on the NFRC label on new windows. The NFRC ratings are for the entire fenestration product (glass and frame combined). Smaller windows have a greater ratio of frame area to glass area than larger windows, which affects the overall rating of the window. For this reason, the NFRC uses standard sizes, residential size and non-residential size, to compare different windows regardless of size.

If you have the NFRC ratings for U-Value and SHGC for a particular window, then you may enter these values in the Custom Window Properties dialog. Be aware that the Glazing and Framing type still play a factor in the calculations and must be entered appropriately.

TREAT calculates the U-value and SHCG for the specific sizes of windows in the building model. The SHGC and U-value for a specific window are not the same as the NFRC rated SHGC and U-value unless the window is the same size as the standard "residential" or "non-residential" sizes used to generate the NFRC ratings. To help determine which Frame and Glazing should be selected from the TREAT Frame Library and Glazing Library to model existing or proposed replacement window that has certain NFRC U-value and SHGC, the table below contains U-value (including film resistances) and SHCG for various window assemblies. All windows in the table are NFRC residential size. Slider type is either horizontal slider or vertical slider.

Shading ranges from 0 if there are opaque blinds covering the window to 1 for clear glass with no external or internal shading. By default the shading factor is set to the value that corresponds to the selected glazing with no additional shading. The meaning of the shading factor (SF) is similar to the shading coefficient (SC) found in the ASHRAE Handbook of Fundamentals; however, the numerical values are not the same. The shading coefficient in the ASHRAE Handbook is defined as the ratio of the solar heat gain through a given glazing assembly to that of a reference single-pane, double-strength, clear (DSA) glass. The shading factor used in TREAT is the ratio of the solar heat gain through the given assembly to the solar heat gain through a similar glazing assembly with clear glass of the same thickness. For glazing systems with only clear glass, the shading factor is one. However, for glazing systems with tinted glass or with selective coatings, the shading factor will have a value less than one.

The shading factor also allows modeling the effects of curtains, Venetian blinds, and various types of external shading devices.

Height above Floor is the height of the window sill above the space floor. The value is used in solar gain calculations if the surface has an overhang.

The Quantity field allows entering multiple windows that belong to the same surface and have the same parameters.

6.5.5 Infiltration

There are three infiltration screens in the program. Navigate to the desired infiltration screen by clicking its title in the Input Panel.

The Heated Area Infiltration screen allows the user to enter combined infiltration of all the heated spaces to exterior and unheated areas. Input may be based on the visual inspection of the building or the blower door test measurements. By default the value is set to Air Changes per Hour based on default building air tightness specified on the Weather/Defaults screen.

The Unheated Space Infiltration screen allows the user to enter infiltration of each unheated space in the project. By default the infiltration is set to 2 ACH for unheated vented spaces and 0.5 ACH to unheated unvented spaces. Modify this value to reflect the actual air leakage. Infiltration input for unheated space is ignored if all the walls in the space are adjacent to "ground".

The Holes in the Building screen allows the user to describe the visible openings in the walls of conditioned spaces. If no input is made on this screen then the value entered on Heated Area Infiltration screen is converted to effective leakage area and allocated to surfaces adjacent to outdoors in proportion with their area. Sealing individual holes can be modeled as an improvement only if the holes are defined on this screen.

6.5.6 Heating/Cooling

TREAT allows specifying main (primary) and back-up (secondary) heating systems. The same thermostat controls both systems. The secondary system is turned on when the primary system capacity is not sufficient to satisfy the building load.

Primary Heating System - click the check box to indicate that there is a primary heating system in the building. This is a required condition for running energy calculations.

Select Heating Type from the drop-down list. The selection tailors the following inputs to the selected type. Set type to Other if your system is not listed in the drop-down box; for example, if it is a wood stove.

Fuel is selected from the list of fuels entered on Fuels/Rates screen.

Specify rated Input Capacity and annual average Efficiency of your heating system in the appropriate boxes.

Annual Efficiency, often referred to as Annual Fuel Utilization Efficiency (AFUE), represents heating equipment performance over an entire heating season. It includes performance during start-up, steady state, and cool-down operations. The AFUE is calculated from performance parameters that are measured experimentally using U.S. Department of Energy (DOE) test procedure. This test includes combustion efficiency, jacket loss, and off-cycle flue loss. Credit is given for design features such as flue dampers. AFUE does not account for electricity consumption and therefore does not include the circulating air (or water pump for boilers) and combustion fan power consumption.

Annual Efficiency of heating system may deteriorate overtime. Use the Calculate Efficiency button open the Heating System Efficiency screen and calculate the annual efficiency of the heat plant.

Steady-state efficiency is the maximum efficiency achieved after a heating system has been running long enough to reach its peak operating temperature. It is equal to the ratio of the heat actually available to the distribution system to the amount of heat potentially available in the fuel. Since Steady-State Efficiency takes into consideration the jacket losses, it is lower than the Combustion Efficiency, but higher than AFUE which accounts for start-up and cool-down losses.

Listed Annual and Steady-state Efficiencies may be obtained from equipment nameplate or manufacturer directory.

In order to obtain Measured Steady-state efficiency for furnaces one has to measure airflow and temperature rise, and for boilers one has to measure water flow and temperature rise, and for both furnaces and boilers one has to measure gas/oil input at the fuel meter. This measurement and the associated calculations are clearly more complicated than a combustion efficiency test.

Actual and listed combustion efficiencies may be entered instead of steady state efficiencies. If, and only if, jacket losses are known or assumed to be very small, which is a reasonable assumption primarily for new furnaces and low-mass boilers, steady state efficiency is close to the combustion efficiency.

Combustion Efficiency is a measurement of efficiency based on the percentage of heat lost up the flue while operating at a steady state condition. Combustion efficiency is determined indirectly, based on measuring flue gas parameters such as temperature and percent carbon dioxide or oxygen.

TREAT relies on the assumption that deterioration in AFUE is proportional to the deterioration in combustion (or steady-state) efficiency. Then, the listed AFUE and listed combustion (or steady state) efficiency and measured actual combustion (or steady state) efficiency may be used to calculate actual AFUE as follows:

AFUE _actual = AFUE _listed × CombustionEfficiency _actual / CombustionEfficiency _listed

A rule of thumb may be used as a last resort when the listed efficiencies are not available. In such cases you may estimate AFUE by multiplying the measured combustion efficiency by 0.85. For example, if the measured combustion efficiency is 75%, the AFUE is around 75% x 0.85 = 64%.

Enter Supply and Return Temperatures and other parameters specific to your heating system.

Year and Location of heating system is recorded for record keeping purposes only.

Secondary Heating System - click the check box to indicate that there is a secondary heating system in the building. This will enable the secondary system inputs, which are similar to primary system inputs.

1. If there is no secondary heat plant in the project or if there is a secondary heat plant and secondary system control is set to operate the secondary system when primary system capacity is insufficient then model heating consumption displayed on the Feedback Panel and in reports is limited by the capacity of the heating system. In this case if the system output capacity is insufficient to satisfy building heating load, the displayed heating consumption will be lower because on cold days the temperature in the building will be less than the specified thermostat setpoint. Check the load sizing report to make sure that the building heating system is not undersized.
2. Low heat plant capacity leads to longer heat plant run time, which may increase distribution loss and hence overall heating consumption.
3. The current version of TREAT does not model the heat plant stand–by loss. Consequently, oversizing the heating system is not penalized.

Secondary System Control input allows describing how the heating load is allocated between primary and secondary system. Two control modes are supported:

Operate when primary capacity is insufficient mode allocates the energy between primary and secondary systems based on primary system output capacity. In this mode secondary system operates only when primary system capacity is insufficient to satisfy building heating load. The percentage of heating energy generated by secondary heating system is different for every month.

Fixed percentage of monthly energy usage mode allocates the energy between primary and secondary system for every month based on fixed percentage entered by user. In this mode energy consumption of primary and secondary heat plants is not limited by system capacities.

Air Conditioning - click the check box to indicate that there is a cooling system in the building.

Total Output Capacity, Btu/hr – specify overall output capacity of the cooling system. If there are multiple room air conditioners in the building, add up their capacity and enter the total in the input field.

SEER/EER –efficiency of the cooling system. Enter capacity-weighted average efficiency if you have multiple room air conditioners.

Type may be set to Central or Room Air Conditioner. The selection does not affect the calculation results.

Number of Units input does not affect calculations. It is used only for the record keeping and reports.

Use the Heating and Cooling libraries to obtain information on typical systems.

The Edit Primary Distribution System button allows the user to customize the distribution system description.

Check the Shared with Cooling box for a forced air distribution system that is used for both heating and cooling. The checkbox is enabled only if a cooling system has been entered.

Estimated Total Distribution Efficiency is used as a starting point for heating energy use calculations. This value is recalculated by the program depending on distribution location (heated/unheated areas), insulation, leakage, etc. The calculated value is displayed in the Design Heating and Cooling Load report.

Insulation R-Value is the R-value of pipe/duct insulation not including air film. Since distribution losses to conditioned space are usually minimal, we recommend entering average R-Value of distribution located in un-conditioned spaces.

Total Area of Piping/Ductwork is the overall surface area of the piping/ductwork. The default is provided based on the total conditioned area in the building. Defaults should be overwritten with detailed site measurements, if available. Diameter and perimeter of the outer surface should be used. Surface area of circular pipe/duct can be calculated as the sum of 3.14 × Diameter × Length for all pipe/duct segments. Surface area of rectangular duct can be calculated as the sum of Cross Section Perimeter × Length for all duct segments.

% Of Piping/Ductwork Running Through Each Space allows allocating the distribution system to spaces entered on the Spaces screen. By default the allocation is done in proportion to floor area of each space at the time the distribution system was first entered. The distribution system allocation may be changed, or it may be reset to default by clicking the Reset % Piping/Ductwork to Default button. The sum of values in each column should always be equal to 100%. The input is used along with distribution leakage and/or insulation to calculate distribution loss and allocate it to spaces through which distribution system is running.

6.5.7 Thermostats

The Thermostat screen is used to group the spaces into heating/cooling zones and enter indoor temperature setting and schedule. Each conditioned space must be assigned to a zone. In the program interface the word zone is used as a synonym of thermostat.

Group of Spaces Served input allows the user to create and edit heating/cooling zones. Click this field to open the Assign Spaces to Thermostats window. The window will not appear if all the conditioned spaces have already been assigned to thermostats. To change the assignment you must first remove the space from the zone to which it was assigned by editing this zone. You may then re-assign this space to a new or existing zone.

The Assign Spaces to Thermostats window allows the user to attach a group of spaces to a single thermostat.

Spaces not served by any thermostat - This area contains the list of spaces that are specified as conditioned but are not yet assigned to a thermostat.

Spaces served by this Thermostat - This area contains the list of spaces that are assigned to this thermostat.

To add a space to the zone, select it in the left panel and click > to move it to the right.
Click >> to move all the spaces in the left panel to the right.
Select a space in the right panel and click < to detach the space from this thermostat.

Click << to detach all spaces from this thermostat. You will not be allowed to close the window if no spaces are assigned to the thermostat (if the right panel is empty), because each thermostat must control at least one space.
Click OK to confirm your selection or Cancel to discard the inputs.

Programmable – select Yes for programmable thermostat and No for non-programmable. The selection applies to both heating and cooling settings (if any) and enables the input fields for setback temperature and time.

Is Area Heated - select Yes if this is a heating or heating/cooling thermostat, No otherwise. The following three input fields will be disabled if you select No.

Occupied Heating Temperature – if you have a non-programmable thermostat, enter its set point here. If you have a programmable thermostat enter its higher setting (set up temperature).

Unoccupied Heating Temperature – the field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat enter its lower temperature setting (set back temperature).

Unoccupied Hours Per Day - the field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat, enter the number of hours per day that the thermostat is set back to its lower setting.

Is Area Cooled - select Yes if this is a cooling or heating/cooling thermostat, No otherwise. The three following input fields will be disabled if you select No.

Occupied Cooling Temperature – if you have a non-programmable thermostat enter its set point here. If you have a programmable thermostat enter its lower setting (temperature when the building is occupied). Unoccupied Cooling Temperature – the field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat enter its higher temperature setting (temperature during unoccupied periods).

TREAT uses the following logic to generate the hourly schedule for space temperature based on specified occupied and unoccupied temperature and hours per day:

1. Temperature for the first 8 "un-occupied" hours is centered on 2 am;
2. Temperature for the second 8 "un-occupied" hours is centered on 2 pm;
3. Temperature for the rest of the day is split between (a) and (b).

Unoccupied Hours Per Day - the field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat enter the number of hours per day the thermostat is set at its higher setting. Use Delete button on Thermostats screen to delete a thermostat. All spaces that were served by the deleted thermostat will be available for a new assignment.

6.5.8 Fans

The Fans screen allows the user to describe mechanical ventilation in the building.

Fan Name is a unique name of the fan.

The Ventilated Area box brings up the Assign Spaces to Fan window. Only conditioned (heated or/and cooled) spaces may be assigned to a fan. Each fan may serve multiple rooms. Each room may be assigned to not more than one fan.

Assign Spaces to Fan window

Heated or Air Conditioned Spaces Not Served by any Fan area contains the list of spaces that are specified as conditioned but not yet assigned to a fan.

Heated or Air Conditioned Spaces Served by This Fan area contains the list of spaces that are already assigned to this fan, along with their floor area entered on the Spaces screen.

The total ventilated area in square feet is shown below the table. The area is updated each time a space is added or removed from the right panel.

Select a space in the left panel and click > to move it to the right and attach to the fan.

Click >> to attach all the spaces in the left panel to this fan.

Select a space in the right panel and click < to detach the space from this fan.

Click << to detach all spaces from this fan. You will not be allowed to close the window if no spaces are assigned to the fan (if the right panel is empty), because each fan must control at least one space.

Click OK to confirm your selection or Cancel to discard the inputs.

Use Delete button on the Fans screen to delete a fan. All spaces that were served by the deleted fan will be available for a new assignment.

Ventilation Rate CFM may only be entered after the Ventilated Area box is filled in. Default value for this field is the CFM equivalent of 0.35 ACH for all rooms served by this fan. To edit the value click the gray area and the Ventilation Rate window will open.

The Ventilation Rate window allows the user to specify ventilation rate in CFM or ACH. Click Convert to ACH (CFM) button any time during the input to convert between the two.

The Ventilation Rate may be entered as total for the fan or on room-by-room basis. To Set Total Ventilation Rate select the appropriate radio button and enter the value. The total ventilation rate is distributed between the rooms that are served by the fan in proportion with the room volume.

To Assign Ventilation to Each Space select the appropriate radio button and enter ventilation rate for each space manually.

Click OK to confirm the inputs or Cancel to discard.

Heat Recovery Efficiency % is entered if a heat recovery ventilator is used. Enter 0 if there is no heat recovery.

Hours per Day Fan is On is the average daily fan run time in hours.

6.5.9 Hot Water

Type – select the appropriate type from the drop-down box. If a space heating boiler is used for hot water (water heater type is Space-heating boiler w/storage tank or Space-heating boiler w/tankless coil) then both heating and non-heating season efficiencies must be entered. Type input is also used for Home Energy Ratings.

Fuel – select a fuel from the drop down box. Any fuel entered on Fuels/Rates screen may be chosen.

Rated Volume and Rated Input Capacity may be taken from the water heater nameplate. Rated volume input is used to calculate jacket loss if the Additional Insulation R-value input is greater than 0 for an existing or proposed water heater. It is also used to calculate annual average efficiency if stand-by loss is entered instead of the energy factor. Rated Input Capacity is used for records only.

Design Supply Water Temperature – the water heater or mixing valve setpoint. This input is used to calculate hot water demand and pipe losses.

Additional Insulation R-Value is used to adjust heater jacket loss and overall efficiency.

Location – select the space where the water heater is located. This input is used to estimate the jacket loss of the water heater. Jacket loss affects heater energy consumption and internal heat gain of the space where the heater is located.

Number of identical water heaters input is used to calculate total jacket loss.

Year is used for record-keeping purposes only.

TREAT uses two efficiency values for water heaters – Recovery Efficiency and either Energy Factor or Stand-by Loss.

Efficiency data for variety of water heaters is available in TREAT Water Heater library accessible from the Water Heater screen. The brand-specific data is available in the GAMA directory at AHRI.

Recovery Efficiency – the ratio of energy delivered to the water to the energy content of the fuel consumed by the water heater.

Energy Factor – a measure of water heater overall efficiency determined by comparing the energy supplied in heated water to the total daily energy consumption of the water heater.

Standby loss is the average hourly energy consumption divided by the average hourly heat energy contained in the stored water, expressed as percent per hour.

The stand-by loss from combination space and domestic hot water heating systems may differ significantly between heating and non-heating seasons. TREAT allows entering two efficiency values for such systems. TREAT uses the input to calculate the average seasonal efficiency taking into account the heating season months entered on the Weather/Defaults screen. Heating season length is assumed to be 6 months if the heating season entered on the Weather/Defaults screen spans more then half the year.

Hot Water Piping box allows describing the domestic hot water piping system.

Insulation R-value is set to 1.5 by default. The value represents average insulation of the piping system.

Total Area of Piping – surface area of hot water piping. The default value is equal to 0.8% of the total area of conditioned spaces. Edit the defaults based on field measurements. The surface area of pipe can be calculated as the sum of 3.14 × Exterior Diameter × Length for all pipe segments.

Set Recirculating System to Yes if there is a hot water loop to make hot water readily available for remote loads. Such systems are mainly used in multifamily buildings. This input is used to estimate hot water distribution loss.

For recirculating systems you can specify the control strategy and the circulating pump capacity. Recirculate When Water Temperature F Falls Below input allows specifying the aquastat setpoint. By default the value is equal to design supply water temperature (no aquastat).

Hours per Day Recirculation is On allows modeling timer-controlled recirculation. By default it is set to 24 hours (no timer control).

Circulating Pump HP allows accounting for energy consumed by the circulating pump. The hours of operation of the circulating pump are calculated using the control strategy inputs. Credit is given for both aquastat-controlled and timer-controlled recirculation.

% Of Piping Running Through Each Space – allocate a percentage of piping to each space in the project. By default 100% of the piping is assigned to the space where the water heater is located (specified in the Location field). The sum of percentages for all spaces in the table should equal 100%. This information is used by TREAT to calculate distribution losses and overheating.

Hot Water Demand area is used to enter or adjust hot water demand.

Usage Adjustment Multiplier allows scaling the hot water demand calculated by TREAT upward or downward. The resulting demand is shown in the Calculated Hot Water Demand box. Click the Calculate button in the box to recalculate demand after inputs are changed. The usage adjustment multiplier is not applied to appliance hot water usage that is specified on the Appliances screen.

If you enter Yes in the Are Dishes Handwashed field, then the usage associated with hand washing of dishes is added to the hot water demand. If there are dishwashers in the building you must enter them on the Appliances screen in order to account for their water usage.

Click the Help button for information on typical hot water demand.

The ASHRAE Handbook of Application gives low, average, and high hot water demand for apartment buildings as 14, 30 and 54 gallons per person per day respectively. It typically varies from a daily average of 42 gal/apartment for buildings with 20 or less apartments to 35gal/apartment for buildings with 200 or more apartments.
Low usage is associated with buildings having such occupant demographics as all occupants working, seniors, middle income, and high population density.

High usage is associated with high percentage of children, low income, public assistance, and no occupants working.

Unfired Storage Tanks button brings up a screen that allows entering hot water storage tank information to account for additional hot water load due to tank stand-by losses.

6.5.10 Lighting

Description – assign a unique name to the lighting fixture or the group of lighting fixtures.

Watts per Fixture – enter Watts per fixture including ballast (if any).

Hours on Per Day – enter average daily usage time for the fixture(s). The input in this field is used to generate the hourly schedule depending on the type of space in which the lighting is located. The hourly schedule for each type of space is as follows:

1. Sleeping Quarters: center hours on 10 pm;
2. Living Space: center hours on 8 pm;
3. Office: center hours on 1 pm;
4. Outdoor lighting : center hours on 10 pm;
5. All other spaces: center half the usage on 7 am and the other half on 7 pm.

According to a pilot study "Incorporating Lighting and Appliance Energy Consumption into the Home Energy Rating Score" prepared by Architectural Energy Corporation, the statistical average connected lighting load in single family houses is 1.25 W/sqft and the lamps are lit on average 2.34 hours/day.

A monitoring project commissioned by the Bonneville Power Administration and Tacoma Public Utilities referenced on LBL website (http://eetd.lbl.gov/btp/papers/38454.pdf, Tribwell and Lerman, 1996) showed similar results, with an average of 2 hours per day operating time and lighting load of 1.47 W/sqft.

When the exact lighting usage in an existing home is not known, the statistical averages presented above should be used to enter the lighting load in TREAT.

Count – enter the number of fixtures in the group.

Location – select the space where the group of fixtures is located or Exterior. Exterior fixtures contribute to the base load calculations but not to the space internal gains.

Copy Lighting From Another Space button opens the Lighting Wizard window. The Lighting Wizard allows the user to copy lighting from one space to the other spaces. It should be used if spaces in the project have similar lighting.

Copy All Lighting From – select the space from which you would like to copy lighting.

To - specify the spaces to which the lighting will be copied.

Every Conditioned Space radio button indicates that the lighting will be copied to each space that was specified as conditioned on Spaces screen.

Every Unconditioned Space radio button indicates that the lighting will be copied to each space that was specified as unconditioned on Spaces screen.

Let Me Pick the Spaces radio button allows user to select spaces to which the lighting will be copied.

Add to already defined lighting in theses spaces radio button indicates that the new lighting will be added to the lighting that may have been already specified for these spaces.

Replace already defined lighting radio button indicates that the new lighting will replace any lighting that has been entered for these spaces.

6.5.11 Appliances

Appliance Name – enter unique name for appliance or group of similar appliances.

Electricity Usage kWh/year – total annual electricity usage. This usage is assumed to be uniform throughout the year. TREAT assumes that appliance usage is distributed uniformly throughout the day.

Electricity Demand Watts – this input is added to support future capability to calculate peak demand load.

Second Fuel – specify a second fuel (if any) used by the appliance from the list of fuels entered on the Fuels/Rates screen. Do not include the hot water fuel in this field. For example, a gas dryer has two fuels – electricity and natural gas. An electric dishwasher does not have a second fuel, even though it may use hot water from a gas water heater.

Annual Second Fuel Usage - total annual usage of the second fuel. The value must be entered in Second Fuel Units per year displayed in the separate field. The units depend on the selected fuel and are the same as on the Fuels/Rates screen for this fuel. The usage is assumed to be uniform throughout the year.

Hot Water Usage gallons/year – annual hot water usage. The usage is assumed to be uniform throughout the year. It is added to the hot water heater load and is accounted for in all calculations related to domestic hot water.

Location – space in which appliance is located. The information is used for internal heat gain calculations.

Percent Heat Loss to Space – percentage of energy supplied to appliance that contributes to space internal gains. Most appliances loose all of their consumed energy to the surrounding space in the form of heat. For these appliances, Percent Heat Loss to Space should be set to 100%. However, some appliances eject part of the heat to the exterior. For example, a clothes dryer heats up air and then discharges it through the vent to outdoors. If you are not sure what to enter in this field look for a similar appliance in the Appliance Library. TREAT assumes that 10% of the heat from the domestic hot water consumed by the appliance contributes to space heat gain.

The Field Measurements button opens the Appliance Metered Usage window. This calculator allows you to easily convert field measurements of energy consumption into yearly figures and copy them into the TREAT Appliances screen. Using a wattmeter and similar tools, you can record the consumption of electricity, second fuel, and hot water during measured time intervals. After entering the measured usage and time interval, click the Done button and the yearly usage will be calculated and copied to the input line for the current appliance.

The Adjust Usage Assumptions button in the Appliance Library opens the Adjust Usage Assumptions window. This calculator allows estimating annual fuel usage by a washer, dryer, dishwasher or cooking appliance based on how frequently the appliance is used. The annual fuel usage given in the appliance library is based on assumptions that are listed in the library, such as a stove being used for two hours each day. To calculate the annual usage if the stove was only used for 15 minutes each day, select the appliance in the library, click the Adjust Usage Assumptions button, and select the correct assumption from the drop-down list. Click the Done button and the revised yearly usage will be copied to the input line for the current appliance.

6.5.12 Load Sizing

Inputs on this screen are used for the Design Heating and Cooling Load report. Edit the values for the primary and secondary heating and cooling system types that are used in the Base Building or evaluated improvements.

Furnace Heating Temperature Drop - design temperature difference between supply and return air temperature. The value is used for duct sizing.

Heat Pump Heating Temperature Drop - design temperature difference between supply and return air temperature used for heat pump distribution system sizing.

Cooling Temperature Drop - design temperature difference between supply and return air temperature used for sizing of cooling ductwork.

Electric Distribution Baseboard Capacity Watt/ft - baseboard capacity per manufactures specifications used to determine the length of baseboard required to meet the space heating load.

Boiler Temperature Drop - design temperature difference between supply and return water. The value is used for pipe sizing.

Hydronic Distribution Baseboard Capacity Btu/hr/ft - baseboard capacity per manufacture specifications used to determine the length of baseboard required to meet the space heating load.

Heating Safety Factor – the value is used to obtain the required heating equipment output capacity as noted on the Design Heating and Cooling Load report.

Cooling Safety Factor – the value is used to obtain the required cooling equipment output capacity as noted on Design Heating and Cooling Load report.

Distribution Safety Factor - specify the safety factor in percent. The value is applied to space distribution CFM/GPM as noted on Design Heating and Cooling Load report.

6.6.1 Visual Inspection

6.6.1 Visual Inspection

This screen allows documenting the result of a visual inspection of the building.

Location drop down box contains a few locations that may require inspection.

Inspection Name input allows assigning custom name to the inspection.

Problem Description: Click the button to display a list of possible problems for the specified location. Check the items that apply to the building. You can also type custom input into the box to the right of the button.

Click the Recommended Action button to display the list of suggested actions. You may also make a custom input in the box to the right of the button.

Repair Cost $: enter the cost to repair.

The default value for Inspection Date is the same as the date of the previously entered inspection. Edit it as necessary.

The Inspection Wizard button opens the Inspection Wizard screen.

6.6.2 Visual Inspection Wizard

The Inspection Wizard is useful when the same inspections are performed for every project. The inspections that were specified on the Preferences screen are listed in the grid of the wizard.

Observations and Additional Notes can be quickly selected for each inspection that you want to add to the project. The check box at the left of the grid can be cleared if you do not want to include that inspection when the Add Selected Observations button is clicked.

The Add Selected Observations button closes the wizard and adds the inspection records with a check mark to the project. The user can enter the repair cost for each inspection, if needed, using the main TREAT interface.

The Preferences button opens the Preferences screen so that the list of included inspections can be changed.

The Cancel button closes the wizard without adding any inspection records to the project.

6.6.3 Measurements

This screen allows you to document the results of measurements taken in the building.

The Location drop-down box contains a few locations that may require measurements.

The Measurement Type input lets you select from a list of types.

The Measured Value and Units are entered as measured.

The Problem Description box allows you to type a description of the problem.

The Recommended Action box is where you enter a short description of the recommended action to address the problem.

The Repair Cost $ box is where you enter the cost of repairs.

The default value for Inspection Date is the same as the date of the previously entered inspection. You can edit it as necessary.

The Measurement Wizard button opens the Measurement Wizard screen.

6.6.4 Measurement Wizard

The measurements that were specified on the Preferences screen are listed in the grid. Measured Value can be quickly entered for each measurement. The check box at the left of the grid can be cleared if you do not want to include that measurement when the Add Selected Measurements button is clicked.

The Add Selected Measurements button closes the Wizard and adds the selected measurement records to the project. It can enter the repair cost for each measurement if needed.

The Preferences button opens the Preferences screen so that the list of included measurements can be changed.

The Cancel button closes the Wizard without adding any measurement records to the project.

6.7.1 General

The Evaluated Options section calculates the energy saving benefits of improvements made to the building envelope, HVAC, domestic hot water system, appliances, lighting, etc.

Improvements are changes to the Base Building components that are described on the Building Model screens. TREAT allows entering multiple options for improving the same existing component.

If you plan to propose multiple improvements to the homeowner, you may group the improvements in several different packages to fit different budgets or payback periods. Interaction between improvements is accounted for when package savings are calculated.

TREAT calculates the following values for each improvement and package in the project:

Cost of improvement is taken from the user input for this improvement. Cost of a package is equal to the combined cost of all the improvements in the package.

Annual Savings MMBtu is the difference between the energy consumption of the Base Building and the building with the improvement. The energy savings are aggregated for all the fuels used in the building.

Annual Savings $ is the difference between the total energy cost of the Base Building and the building with improvements.

Payback, Years is the number of years it will take for the Improvement or Package to pay for itself. It is calculated as a ratio of the improvement cost to the annual dollar savings.

SIR (savings to investment ratio) allows the user to perform a more accurate economic analysis of the improvement feasibility. It compares two alternatives: investing in the improvement versus investing in a bank CD at the specified rate for the term equal to the life of the improvement. The SIR value accounts for inflation. An SIR greater than one indicates that the improvement makes economic sense.

SIR is calculated as the ratio of adjusted savings to the investment (cost) of improvement or package. Adjusted improvement savings are calculated using the following formula:

• A- calculated improvement $ savings shown on Improvements screen
• N - improvement life entered on Improvement Wizard screen and shown on Improvements screen
• e - inflation rate entered on Edit Financial Information screen
• i - bank rate entered on Edit Financial Information screen.

The adjusted package savings are calculated as sum of adjusted improvement savings.

Cash flow is a feature of the Packages screen, not the Improvements screen. Cash flow is useful when the homeowner has to borrow money from the bank to pay for the improvement. Cash flow is calculated as the difference between the annual improvement savings and the loan payments.

6.7.2 Improvements

The Improvements screen allows the user to create, edit or delete proposed improvements, calculate energy and dollar savings from improvements, and edit financial information. The screen displays the list of improvements created by the user.

Select an improvement and click the Calculate Improvement button to run the calculations for it. Click the Calculate All Improvements button to run the calculations for all improvements on the screen for which calculations have not been performed yet.

The Edit Financial Information button opens a window that allows the user to modify the values that are used to calculate SIR (Savings to Investment Ratio) and cash flow.

The Lifestyle Savings button opens the Lifestyle Savings screen described separately.

You need to remove an improvement from all the packages that include it before you can delete the improvement on this screen.

6.7.3 Improvement Wizard Step 1

Click the Add Improvement button to create a new improvement and open the Improvement Wizard Step 1.

The wizard presents the list of the improvement types that may be modeled in TREAT and guides you through the data input screens that need to be filled out. The following types of improvements are available:

Appliance Replacement: remove existing appliance(s) and/or add new one(s).

Cooling System Improvement: replace existing cooling system.

Distribution System: improve existing heating or central cooling distribution.

Domestic Hot Water Improvement:

• Water Heater Replacement
• Water Heater Insulation
• Water Heater Setpoint Adjustment
• Hot Water Piping Insulation
• Low Flow Device Installation
• DHW Storage Tank Improvement
• Recirculation Control Improvement

Door Replacement: replace existing doors.

Fan Improvement:

• Modify existing mechanical ventilation fan(s).
• Add new fan(s).
• Remove the fan(s) identified in the Base Building model.

Heating Control Improvement: add a reset control to the existing boiler.

Heating Plant Improvement: replace the existing primary or back-up heat plant.

Indoor Temperature Control: install a programmable thermostat or change thermostat settings.

Infiltration Improvement:

• Reduce total infiltration of heated spaces.
• Reduce wall leakage specified in Holes in the Building section of Infiltration screen.
• Reduce infiltration of unheated spaces defined on Spaces screen.

Lighting Replacement: replace the lighting specified on the Lighting screen.

Measurements: improve the measurements described on the Measurements screen.

Surface Insulation: change insulation and construction of surfaces described on the Walls/Surfaces screen.

Visual Inspection: improve problems described on the Visual Inspection screen.

Window Replacement: replace existing windows entered on the Windows screen.

Improvement types are listed in alphabetical order. Use the mouse to select an improvement type and click Next to open the Improvement Wizard Step 2 window. Click Cancel to close the Improvement Wizard window and return to the Improvements screen.

6.7.4.Improvement Wizard Steps 2 and 3

The interface of Improvement Wizard Steps 2 and 3 depends on the improvement type that you have selected. Generally, you will need to enter the following information:

Improvement Name is generated by TREAT and may be edited by user.

Improvement Life is by default set to a typical value for the selected improvement type. The input is used in SIR calculations and may be adjusted by the user as necessary.

Improvement cost may be entered as total cost or unit cost. Total cost input is available for all improvement types. In addition to that, for some improvements the user may choose to enter unit cost instead of total cost by making appropriate selection in Improvement Cost Methods combo box. If unit cost method is selected, then entered unit cost will be automatically adjusted as quantity of improved components (e.g. replaced windows) is changed. Total cost is independent of other improvement inputs.

The Edit Workscope button allows selecting a workscope from the library or entering a custom workscope. The current version of TREAT does not allow saving custom workscopes to TREAT library. However, you may save your workscope in a word processor and paste it into TREAT when needed.

The Done button saves the inputs and closes the Improvement Wizard.

The Cancel button closes the Improvement Wizard without saving any information.

Enter the information required for each improvement type in the white boxes. Most screens also display the relevant information for the Base Building against a gray background. This information may be edited on Building Model screens where it was entered.

Appliance Improvement is used to add or remove appliances. If you want to remove existing appliances, move them from left to right in the top panel. The lower panel allows the user to specify new appliances. The interface is similar to the Appliances screen of the Building Model section.

Specify a new cooling system on the Cooling System Improvement screen. Total output capacity, average SEER/EER, type and design supply temperature inputs are used in energy calculations. Number of New Units installed is used with the specified cost of a new unit to calculate the total improvement cost. The rest of the cooling system inputs are for record keeping and reports. For a central cooling system you may edit distribution system defaults generated by TREAT. If the existing heating or cooling system has forced air distribution, then this distribution system may be reused for the new cooling system.

Distribution Improvement - Select the existing distribution system that you want to improve on the Improvement Wizard Step 2 screen. As noted above, you will not be able to combine in one package a distribution improvement and a heating or cooling system improvement. Use a Distribution Improvement only if you need to evaluate the effect of improving a distribution system without making any upgrades to existing heating plant or AC system. The screen allows the user to specify new values for all the parameters of the existing distribution system. See the Heating/Cooling screen section for more details on distribution system inputs.

The Domestic Hot Water improvement screen is only available if an existing DHW system was entered on the Hot Water screen.

Water Heater Replacement allows you to specify a new water heater. Inputs are the same as on the Hot Water screen of the Building Model section.

The Hot Water Heater Insulation screen allows you to model the effect of wrapping an existing hot water heater with an insulating blanket.

The Water Heater Setpoint adjustment screen allows you to model turning down the water heater temperature.

The Hot Water Pipe Insulation screen allows you to model the savings associated with losses from domestic hot water piping.

The Low Flow Device Installation screen allows you to model the savings associated with reduction in hot water flow rate due to installation of new plumbing fixtures. Savings from reducing waste in overall water usage is not included in this improvement.

The left side of the Door Replacement screen contains the list of doors entered on the Exterior Doors screen. If you have multiple doors in the project you may filter them using the search criteria at the top of the left panel. You may replace existing doors of different construction with the new doors that have the same construction as one improvement. Create a separate improvement for each unique door type that you plan to install. TREAT does not allow adding or removing doors or changing door dimensions. Savings are calculated only based on specified new door U-value.

Fan Improvement allows modifying an existing fan by adjusting its ventilation rate, schedule and heating recovery efficiency, removing an existing fan, or adding a new fan.

Heating Control Improvement allows the user to model savings from installing a Reset Control on the existing boiler.

Heating Plant Improvement allows the user to model installation of a new primary or secondary heat plant. The new heat plant may share distribution with existing heating or cooling or have a new distribution system. If a new distribution system option is selected, you may edit the default distribution settings by clicking the Edit Distribution button. A Heating Plant Improvement should be used if a modification or maintenance work is proposed for an existing system that will change the vital system parameters.

Indoor Temperature Control Improvement allows the user to modify the setpoints and schedule of thermostats specified on the Thermostats screen. The most common improvement of this type is programmable thermostat installation. You may also use this improvement to model overheating in the building due to unbalanced distribution. Modeling of overheating due to distribution loss, high base/occupant internal gains and domestic heater stand by loss does not require creating zones with artificially high thermostat setpoint – it is automatically calculated by TREAT.

Infiltration Reduction allows the user to specify reduction of the total infiltration of heated or unheated space and/or wall leakage entered on the Infiltration screen. This improvement type should be used to model weather-stripping, sealing of the building envelope and infiltration reduction due to door and window replacement.

The Lighting Replacement improvement allows the user to replace various existing lighting fixtures with new fixtures of the same type.

The Measurement improvement helps to specify the work that needs to be done to improve the problems that were uncovered through various measurements taken during the site visit. You need to have the measurement entered on the Measurements screen in order to be able to specify it as an improvement. TREAT does not calculate the energy savings associated with the measurement improvement. It assumes that the improvement is done to improve indoor air quality and/or occupant safety and comfort.

The Surface Insulation improvement allows the user to model any upgrades to existing walls, floors, ceilings or roofs. Use the filter in the left portion of the screen to find the existing surfaces that you would like to improve. You may then move the surfaces to the right panel and specify the single new construction of the improved surface. Note that the current version of TREAT does not allow adding insulation to the existing surface. However, you may easily model it by specifying the proposed surface description that reflects the insulation level of the wall after improvement. Note that you may not change surface size or orientation as part of the improvement.

A Visual Inspection improvement may only be created for inspections entered on the Visual Inspection screen. Similar to the measurement improvement, there are no energy savings associated with this improvement type. The non-energy benefits of this improvement will be shown in the reports for the package that contains this improvement.

The Window Replacement improvement allows the user to model replacement of existing windows. You may change multiple windows to the new window type (frame and glazing) in a single improvement. Note that any infiltration reduction associated with window replacement should be entered separately as an infiltration improvement. If you have the NFRC ratings for U-Value and SHGC for a particular window, then you may enter these values in the Custom Window Properties dialog. Be aware that the Glazing and Framing type still play a factor in the calculations and must be entered appropriately.

6.7.5 Lifestyle Savings

The improvement wizard screens described above allow entering physical improvements to the building that are usually installed by professionals, such as replacing heating system, installing programmable thermostats, insulating an attic, etc. However, some of the energy savings may be achieved by simple changes in the lifestyle of building occupants. Turning off lights in the room when leaving, reducing shower times, replacing the furnace filter regularly, cleaning refrigerator coils and other similar actions can often produce significant energy savings with minimal or no investment.

TREAT allows estimating energy savings from occupant behavior by associating variety of lifestyle actions with each improvement entered on the Improvement Wizard screen. The inputs are made on the Lifestyle Savings window, which is accessible from the Improvements or Packages screen by clicking the Lifestyle Savings button.

The screen is divided in two sections. The upper table is non-editable and shows all improvements in the project or in the selected package, depending on the setting of the filter at the top of the screen. The lower table allows editing inputs for the selected improvement.

Only Improvement Name and improvement type are shared between "physical" and "lifestyle" inputs for any given improvement.

Improvement Category is the drop down box with the options appropriate for the selected improvement. The category helps to filter the internal TREAT lifestyle action database to display only those actions appropriate for the current improvement. Some improvement types have a single Improvement Category, for example Heat Plant Replacement has only one category - Heating. Appliance Replacement, on the other hand, has multiple categories available for selection, with each category corresponding to a major appliance type.

Total lifestyle action cost is different from the improvement cost entered on the Improvements screen and represents only lifestyle-related expense. For example, you may model furnace replacement in TREAT and enter the cost of the furnace installation on the Improvement Wizard screen. In addition to that, you may want to educate user regarding importance of regular filter replacement. You may enter filter replacement as a lifestyle action and associate separate cost with it.

The second row of drop down boxes in the lower part of the screen allows specifying the algorithm for calculating lifestyle savings of the selected improvement. The accuracy of lifestyle–related savings is lower than savings from physical improvements to the building because occupant behavior changes with time and there are often no reliable algorithms to predict how certain behaviors affect energy consumption. TREAT uses a simplified approach to lifestyle savings calculations. The user selects the end use to which the savings percent is applied, such as heating, cooling, domestic hot water or usage of fixtures included in the improvement. TREAT then calculates the savings as percent of energy usage for the specified end use in the existing building or in the current improvement. The algorithm options depend on Improvement Category.

For appliance and lighting improvements, the value of heating/cooling interactions is estimated using actual heating and cooling system efficiencies, appliance/lighting location and percent loss to space. An assumption is made regarding heating/cooling season length. If there is cooling in the project, then for the purpose of lifestyle savings each space is assumed to be both heated and cooled. Interaction between improvements in packages is not accounted for.

After Improvement Category is selected, the lower table is filled with default lifestyle actions. You may edit the name of each Lifestyle Action, change Estimated Savings % and toggle Accepted

and Possible fields. The Total Savings percentage in the lower table is updated as you change the inputs. Once improvement data is finalized, save it with the Save button. The Reset to Defaults button cancels all the changes made in the lower table and reverts to default information for the selected Improvement Category. When information in the lower table is saved, the list of accepted lifestyle actions is copied to the upper table.

Accepted and possible savings may be calculated using the two buttons at the bottom of the screen. You must run model calculations for the base building and improvement packages before running lifestyle savings calculations. Inputs on the lifestyle savings screen do not affect improvements and packages cost and savings on any other TREAT screen. The lifestyle savings are summarized on Occupant Lifestyle Savings report.

6.7.6 Packages

The Packages screen allows the user to group the improvements created on the Improvements screen. This screen displays all the packages in the project. You may add, edit or delete existing packages and calculate package energy and dollar savings.

Select a package and click the Calculate Package button to run the calculations for it. Click the Calculate All Packages button to run calculations for all the packages you created.

The Edit Financial Information button opens a window that allows the user to modify values required to calculate SIR and cash flow.

Select a package and click the Delete Package button to remove it. Note that this does not delete the improvements created on Improvements screen and included in the package, it just deletes the way that they are grouped.

To create or modify a package, click the Add Package and Edit Package buttons to open the Package Wizard screen.

Copy Package button creates a copy of the selected package.

Edit the default package name in the Package Name box.

Annual Savings $, Payback Years and SIR presented for each Improvement on the Package Wizard screen are adjusted to account for interaction between improvements in the package. These values are different from the non-interacted, independent values presented on the Improvements screen for the same improvement.

TREAT uses the following steps to estimate interacted savings:

1. Calculate BTU savings for each improvement in the package. Savings for each fuel and each end use are calculated separately. The end use categories in TREAT are heating, cooling, lighting, appliances, domestic hot water and other. The other category includes such uses as a circulation pump for domestic hot water. If there are two fuels in the project, then 6(end uses) × 2(fuels) = 12 values are calculated for each improvement.
2. Add up the savings for each end use and each fuel calculated in the previous step for all improvements in the package. These values represent the total package savings without accounting for interaction of improvements in the package.
3. Calculate BTU package savings for each fuel and each end use by subtracting the corresponding package usage from the base building usage. These are the actual savings in the package that include interaction.
4. Calculate the interaction penalty for each end use and each fuel by dividing package savings that include interaction (that were obtained in step 3) by non-interacted package savings that were obtained in step 2.
5. Interacted improvement savings are calculated for each fuel and each end use as the product of the individual improvement savings calculated in step 1 and the interaction penalty from step 4. The individual values are then added together to obtain the total interacted improvement savings.

To create a new package, click the Add or Remove Improvements in this Package button. A new window will open.

The left panel of the window contains all the improvements in the project that are not yet included in this package sorted by the SIR value. The right panel contains improvements that are already included in the package. Total cost of the package is shown at the bottom of the right panel. Move the improvements that you want to include in this package to the right panel. Click the Save button to save your selection, create the package, and close the window.

TREAT verifies that the improvements in the right panel can be combined in a single package. For example TREAT will display an error message and will not save your selection if you have mistakenly included two primary heating system replacements in a single package.

7.1.1 Standard Reports screen

TREAT offers a wide variety of reports to assist you in the modeling process and demonstrate the improvement benefits to the building owner. Reports may be accessed from the Index Panel or the main menu, under Reports. Most of the reports become available only after a project is opened and has calculated results.

Select the checkbox next to the name of the report to indicate that you would like to view it. Depending on the report that you select, you may be asked for some additional information that is required for the report. Note that your inputs on this screen are not saved with the project.

The Change Selection button on the Reports window allows the user to change the package or analysis period for which the report is created. Click the View button if you would like to view the report. Click the Print button to print the report without viewing. You may also print the report directly from the on-screen report (also called the print preview window), using the buttons at the top of the screen.

Reports may be saved to a file using the Save shortcut on the print preview toolbar. Any TREAT user may open the file with the Open shortcut on the print preview window.

Base Load and Occupant Lifestyle Savings reports may be printed without headers. Click Reports > Use paper with pre-printed headers on the main menu and check the name of the report for which you would like to use this option.

The Fuel Bill Release report prints a letter to the utility company requesting that they release the bills for a specified address.

Building Description shows all the inputs made on the Building Model screens.

The Design Heating and Cooling Load report presents results of the load sizing calculations. TREAT load sizing has been tested in Minimize Calculation Time mode and results were compared to Manual J. TREAT heating and cooling loads proved to be slightly more conservative. Please use professional judgment in applying the results to sizing heating and cooling systems.

The Model Energy Report presents two pie charts for the selected package or the Base Building:

1. A breakdown of the total energy bill by end use category including heating, cooling, lighting, appliances and hot water.
2. A breakdown of the heating/cooling energy bill by category including infiltration, loss through windows, surfaces and mechanical ventilation.

This report is available for any calculated package or the Base Building.

The Base Load Report provides information on energy consumption by appliances, domestic hot water and lighting in the selected building model. This report is available for models with calculated results. If the model is compared to more than one analysis period, you will be asked to select a single analysis period for inclusion in the report.

The Occupant Lifestyle Savings report contains information from Lifestyle Savings screen. This report is made up of two parts – one part summarizes possible savings, the other part shows savings accepted by the home-owner. The main purpose of the report is to educate homeowners about potential of energy conservation behaviors.

The Model to Actual Comparison of Base Usage table shows the overall non-HVAC energy consumption of each fuel in the selected model and billing analysis period (if any). The percent difference row indicates how well the model base load was calibrated against billing data.

The Base Load Report gives a detailed report on base load energy consumption. The items in this table are sorted by total annual cost of consumed fuel. The top nine energy consumers are shown individually, and the rest of the items are aggregated and presented in a single Other category.

The Percentage Improvement report compares annual energy savings of the selected packages with the overall energy usage of the Base Building.

The Visual Inspection and Measurements reports display the inputs made on the corresponding screens of Building Inspection section.

The Visual Inspection / Measurements Forms report prints the requested number of forms for on-site data collection. The forms closely resemble the Visual Inspection and Measurements screens.

The Improvement Packages report displays the calculation results presented on the Package Wizard screen for the packages selected by the user. The report includes the list of all non-energy benefits of improvements in each package.

The Workscopes report contains the list of the work scopes for the improvements in the selected package.

The Normalized Model to Billing Comparison report presents tabulated energy consumption of each fuel for the model and the corresponding billing analysis period. The billing period fuel usage is calculated using the slope and reference temperature from the billing analysis and thirty-year average weather data. The report is available for the analysis periods that are compared to a Base Building or a package.

Investment Guidelines for Heating provides an estimate of the cost-effective investment based on the billing analysis slope, reference temperature, cost of heating fuel, target payback and several other criteria. The report is presented for any billing analysis period for which calculations were performed.

The Heating Energy Scorecard presents a bar chart comparison of the overall annual per square foot energy usage of your building and energy usage of typical new and existing homes.

The Normalized Annual Billing Savings Tracking report compares the energy usage of the two selected analysis periods. For each period it presents stacked bars for each fuel, providing a breakdown for heating, cooling and base load. Heating and cooling consumption is calculated based on the heating and cooling slope for the period and the thirty-year average weather data.

The Actual Billing to Model Comparison report displays side by side the average daily fuel usage from each utility bill included in the analysis period and the calculated model usage for the same period. The report is available only for the fuels with the single set of billing data, not for the fuels with multiple individually metered spaces. The actual weather conditions during the billing period and the calculated model slope are used to generate the model usage data.

The Customer Information and Mail Merge report allows using the customer data entered in TREAT to generate a customer list in the comma-delimited text file format. This file may be used for printing letter headings, mailing labels and for other administrative and marketing activities.

The Data Collection Forms report prints the forms that should be used for data collection during site visits. The forms very closely resemble the input screens of the Building Model section. Enter the estimated number of spaces in the building, which allows TREAT to evaluate the expected number of walls, windows and lighting in the project and allow enough space on the forms.

7.4.1 NY Home Performance

TREAT offers two customized reports for NY Home Performance program. These reports may be accessed by selecting Custom Reports > NY Home Performance on the main menu.

The Home Performance Report may be used to present the modeling results to the building owner. Its purpose is to demonstrate the energy, health and safety benefits of up to three suggested packages for which modeling calculations were performed. The report contains educational information on the different types of improvements and a summarized description of the Base Building and proposed measures. The total cost, energy savings, payback and SIR of each package is shown to illustrate the feasibility of the improvements.

The Workscope Upload report allows the user to save the information for a single selected package to two files that conform to NYSERDA reporting requirements and may be uploaded to a NYSERDA database using an exporting tool that is shipped separately from TREAT. The export files are named [ProjectName_PackageName.txt] and [ProjectName_PackageName.xml] and are saved to the NYSERDAReporting folder located in the TREAT root directory.

You may export any package that has calculation results for all the included improvements.

If you run the report several times for the same project, then the later file will overwrite the earlier file. Only one file per project may be stored. You may create files for multiple projects without overwriting the information.

8.2.1 Step 1: Create the file to import

Enter, or select, the text file with billing data. The file may be created by the user or downloaded with TREATtracker. TREATtracker files are ready for import into TREAT.

Each line of the text file must contain comma-separated data for a single utility bill in the following format:

FuelID, Account#, StartMonth, StartDay, StartYear, ElapsedDays, $Usage, UnitUsage, IsBillEstimated

FuelID - numeric identifier for the fuel from the Fuel Table below
Account# - billing account number
StartMonth - month from 1 to 12 corresponding to starting date of utility bill
StartDay - number from 1 up to maximum number of days in the StartMonth

StartYear - four digit positive number
ElapsedDays - number of days in the bill, may be any positive whole number
$Usage - dollar cost of fuel consumed during the billing period (any positive number)
UnitUsage - amount of consumed fuel in units of fuel. Units of fuel are determined by FuelID.
IsBillEstimated - enter TRUE for estimated bills and FALSE for actual bills.

Blank lines are acceptable, and comments can be added to the data by starting a line with two dashes (--). Files downloaded from TREATtracker do not require any modifications.

Fuel Table

Sample File

    -- This is a Billing Import file for 123 Main St.
    -- The next lines show the names of the data in each column
    -- FuelID, AccountNumber, BillStartMonth, BillStartDay, BillStartYear, ElapsedDays, UsageDollar, UsageUnitsOfFuel, IsEstimated
    -- FuelID 5 is "Electricity, kWh"
    5, 	apt 1,	5, 	1, 	1998, 	31, 	90.83, 	616, 	FALSE
    5, 	apt 1, 	6, 	1, 	1998, 	30, 	99, 	627, 	FALSE
    5, 	apt 1, 	7, 	1, 	1998, 	31, 	104.14, 715, 	FALSE
    5, 	apt 1, 	8, 	1, 	1998, 	31, 	110.58, 763, 	TRUE
    5, 	apt 1, 	9, 	1, 	1998, 	30, 	89.5, 	612, 	FALSE
    5, 	apt 1, 	10, 	1, 	1998, 	31, 	85, 	546,	FALSE

    5,	apt 2, 	5,	1,	1998,	31,	45.42,	308,	FALSE
    5, 	apt 2, 	6,	1,	1998,	30,	48,	312,	FALSE
    -- the next two bills will both be rejected because they overlap each other
    5, 	apt 2, 	7,	1,	1998,	32,	52.1,	357,	FALSE
    5, 	apt 2, 	8,	1,	1998,	31,	55.29,	381,	FALSE
    5, 	apt 2, 	9,	1,	1998,	30,	44,	306,	FALSE
    5, 	apt 2, 	10,	1,	1998,	31,	42.37,	271,	FALSE

    --FuelID 15 is "Propane, Gallon"
    15,	apt 1,	5,	1,	1998,	31,	75.00,	100.35,	FALSE
    15,	apt 1,	6,	1,	1998,	30,	150,	200.9,	FALSE
    15,	apt 1,	7,	1,	1998,	31,	225,	300.6,	FALSE
    15,	apt 1,	8,	1,	1998,	31,	187.56,	250,	FALSE
    15,	apt 1,	9,	1,	1998,	30,	160,	220,	FALSE
    15,	apt 1,	10,	1,	1998,	31,	135,	180,	FALSE

    15,	apt 2,	5,	1,	1998,	31,	90.83,	616,	FALSE
    15,	apt 2,	6,	1,	1998,	30,	99,	627,	FALSE
    15,	apt 2,	7,	1,	1998,	31,	104.14,	715,	FALSE
    15,	apt 2,	8,	1,	1998,	31,	110.58,	763,	FALSE
    15,	apt 2,	9,	1,	1998,	30,	88.3,	613.08,	FALSE
    15,	apt 2,	10,	1,	1998,	31,	84,	542.00,	FALSE

8.2.2 Step 2: Match account numbers with metered spaces

This screen allows you to match up account numbers included in the text file with the individually metered spaces entered on the Metered Spaces screen. If all the bills for a fuel in the text file are for the same account number, you will be asked if this is the only account number for this fuel. If the building has a single set of utility bills for this fuel, answer Yes, otherwise answer No.

If there are multiple account numbers for a fuel, the Billing Import Utility displays the table with two columns. The left column contains the list of account number(s) for this fuel found in the import file. The right column contains the name(s) of individually metered space to which the bills for this account number will be assigned in TREAT. By default the names of individually metered spaces are the same as the account numbers. You may change the default space name by typing in a new name or selecting a name of an existing metered space.

8.2.3 Step 3: Copy data from the file to the TREAT database

Bills for the same account and the same fuel within the import file must not overlap with each other or with the bills already entered in TREAT. TREAT reads the import file and determines if some of the bills in the file overlap the bills previously entered in TREAT. If such bills are found, then TREAT asks if you want to overwrite existing bills with new ones. If you click Yes then all previously saved bills that are at least partially overlap imported bills will be deleted and the new bills will be imported. If you click no, then no bills that at least partially overlap existing bills will be imported.

8.4.1 Inspection Summary page

The Inspection Summary gives an overall count of the warnings on each page of the Model Inspector. This tab also shows monthly energy usage broken up by fuel type and end use if calculation results are available for the selected model.

8.4.2 Building Envelope page

In order to obtain accurate modeling results it is important to enter all surfaces through which heat is transferred in and out of the building. Model Inspector runs the following verifications of the building envelope input:

1. There is roof or ceiling adjacent to outdoors.
2. There is floor adjacent to outdoors or ground.
3. Total floor area is within 10% of the area of horizontal projection of roof/ceiling. The horizontal projection of the roof is calculated using roof tilt in degrees and the area of the roof surface in sq ft.
4. The area of all exterior surfaces in the project is not less than the surface area of a cube of the same volume as the building. The building volume is calculated as the sum of volumes of all spaces in the project. Space volume is calculated as the floor area multiplied by ceiling height.
5. The R-value of all walls in conditioned space that are not adjacent to ground is at least R-4.
6. Windows in conditioned spaces do not have single-pane glass.
7. All heated spaces have window area of 10% to 40% of floor area, which is typical for residential construction.
8. All unconditioned spaces have at least one surface adjacent to a conditioned space. Surfaces between conditioned and unconditioned spaces are entered in TREAT as attached to conditioned space and adjacent to unconditioned space. Unconditioned spaces that are not connected to conditioned spaces will be heated only by space heat gain from base load located in these spaces (such as lighting). This may result in unexpectedly low indoor temperature in these spaces and exaggerated losses from sections of distribution system located in these spaces. Heat exchange between unheated spaces and heated space(s) in the project will not be accounted for. Check the Calculation Results tab of the Model Inspector to make sure that the temperature of unheated spaces is close to what you observed during the site visit.
9. All unconditioned spaces have a surface adjacent to outdoors. This is important if "Surface Leakage Proportional to Area" infiltration algorithm is selected on Weather/Defaults screen. In this case the infiltration input for unconditioned spaces with no surfaces adjacent to outdoors will be ignored and the resulting building heat loss may be significantly underestimated
10. Infiltration of conditioned spaces is between 0.2 and 2 ACH, which is typical of residential construction.
11. If "Leakage allocated in proportion to surface area" is selected as the infiltration algorithm on the Weather/Defaults screen, then area of holes in the building should account for at most 10% of overall building infiltration. Due to the nature of algorithms employed in the detailed infiltration calculations, the accuracy of modeling results may be compromised if area of holes in the building accounts for more than 10% of overall building infiltration.

8.4.3 Lighting/Appliances page

The following verification of lighting input is performed: The lighting in conditioned spaces is within 20% of the average Wh/SqFt/Day as entered on the Weather/Defaults > Advanced screen. The default value that the Model Inspector uses for the average is 3 Wh/SqFt/Day if a different value has not been entered.

According to a pilot study "Incorporating Lighting and Appliance Energy Consumption into the Home Energy Rating Score" prepared by Architectural Energy Corporation, the statistical average connected lighting load in single family houses is 1.25 W/sqft and the lamps are lit on average 2.34 hours/day.

A monitoring project commissioned by the Bonneville Power Administration and Tacoma Public Utilities referenced on LBL website (http://eetd.lbl.gov/btp/papers/38454.pdf, Tribwell and Lerman, 1996) showed similar results, with an average of 2 hours per day operating time and lighting load of 1.47 W/sqft.

Both studies yield similar daily lighting usage of around 3 Wh/SqFt/Day. This usage is used by TREAT as default. You may modify the default on the Advanced window of the Weather/Defaults screen.

Another helpful link for determining the lighting load of particular building is http://www.eia.doe.gov/emeu/lighting/contents.html, which opens a document prepared by Energy Information Administration Office of Energy Markets and End Use of U.S. Department of Energy. The paper presents data on typical lighting energy usage in various residential building types. According to the study, the most of apartments (32.9 percent) consume between 250 and 499 kWh/year. The largest number of mobile homes (24.0 percent) consume between 500 and 749 kWh/year. Among single-family homes, the consumption is higher, with 17.4 percent using between 750 and 999 kWh/year.

The following verification of appliance input is performed:

1. A summary of the annual appliance usage of each fuel.
2. There are appliances that use hot water. Typical residential buildings have some appliances, such as clothes washers and dishwashers, which use hot water. Omitting them may result in incorrect DHW consumption.

8.4.4 HVAC page

The following verifications of input data related to heating, ventilation and air conditioning are performed:

1. Room air conditioners, if present, are not being used to cool the entire building. Typically room air conditioners service only part of a building.
2. Room air conditioners, if present, are not maintaining the same thermostat setpoint 24 hours per day. Typically room air conditioners are turned off during part of the day. This usage pattern may be modeled in TREAT by entering programmable thermostat with high setback temperature.
3. Central air conditioning, if present, is being used to cool all conditioned spaces in the building, which is typical for most of the installations.
4. There is a domestic hot water heater in the building. DHW affects heating and cooling load through stand-by losses. Omitting it will also interfere with model/billing calibration, especially if heating/cooling and DHW fuels are the same.
5. The domestic hot water heater is located in unconditioned space, which is typical of most buildings. Note that if DHW heater is located in conditioned space, then its stand-by loss will contribute to useful heating of the space.
6. There is mechanical ventilation in the building. Residential buildings typically have kitchen or bathroom exhaust fans that are used occasionally. Multifamily buildings often have ventilated common spaces.
7. The mechanical ventilation for each space is below 0.5 ACH. Ventilation rate over 0.5 ACH is in excess of typical residential applications.
8. If the primary and secondary heat plants are located in different spaces, there will be a warning reminding that both heat plants heat the entire conditioned space. The secondary heat plant is modeled in TREAT as operating only when the capacity of the primary heat plant is not sufficient to satisfy heating load.
9. Combustion efficiency for boilers and furnaces should be measured. The annual efficiency entered into TREAT for boilers and furnaces should be below the measured combustion efficiency.

8.4.5 Calculation Results page

If calculation results are available for the base building or improvement package, the following verifications are performed:

A Package does not save more than 50% of the energy used by the Base Building.

The heating system is not undersized. If the heat plant is undersized, then the living space will be cooler than the thermostat setpoint temperature during cold weather, and energy usage of the building will be underestimated. For detailed information on heating load view the Design Heating and Cooling Loads Report.

The heat plant output exceeds the building load by the safety factor specified on Load Sizing screen. This will not affect modeling results. Since heating systems are usually sized conservatively, this may serve as a warning that building heat loss or heating system losses are overestimated.

The heat plant output adjusted for the safety factor does not exceed the building load by more than 50%. If it does, it may indicate that building heat loss or heating system loss is underestimated – for example not all surfaces/windows have been entered, useful heat loss from heating /DHW system/appliances is overestimated, infiltration is underestimated, heating/distribution efficiency is overestimated, etc.

Heating distribution system efficiency is at least 60% for primary and secondary distribution systems, which is typical for residential applications. It is also important to check that estimated distribution efficiency entered in distribution window of Heating/Cooling screen does not differ significantly from calculated distribution efficiency shown on Design Heating/Cooling Load report. If the difference is large, enter estimated distribution efficiency equal to calculated distribution efficiency and recalculate the project.

The heating reference temperature is at least 50 F. If the outdoor temperature is below 50 F, a typical residential building should require heating.

The cooling reference temperature is at least 70 F. Typical residential buildings should not require cooling if the outdoor temperature is below 70 F.

Calculated heating slope is in the typical range. It usually varies from 2 Btu/HDD-SqFt for best new construction to 25 Btu/HDD-SqFt for high usage existing home. Note that the limits may be different for your housing type.

At least 500 HDD or CDD were used to calculate the Heating/Cooling slope. Heating/Cooling Slope may not be accurate if actual HDD/CDD are low since actual weather data in not available on hourly basis.

Cooled spaces can usually take advantage of free cooling provided by natural ventilation, which may be entered on the Advanced window of the Spaces screen. Natural ventilation is modeled only during the months that are not part of the heating season. Heating and cooling seasons are entered on the Weather/Defaults screen.

A table is displayed with the calculated average monthly temperatures of each unconditioned space. The temperature depends on the heat transfer through exterior surfaces, heat exchange with adjacent heated spaces, internal gains from lighting and appliances. It does not account for internal gains from heating or DHW systems, if any. Make sure that the temperatures are close to the ones measured during the site visit.

9.1.1 Converting Treat Project Group files into Project Group Templates

To convert a TPG file to a template, save it as a template. The new template will be open in TREAT.

9.1.2 Step 2: Create a new project group using the template

On the Project Group > New menu select the Use Template option. Select the appropriate template from the Select a Template window. This will create and open a new Treat Project Group with the same contents as the selected template.

Partial cooling is common and is often not modeled correctly. Users may adjust the template or create new templates with two conditioned spaces – heated only and heated/cooled.

Edit the modeling inputs within the project to accurately represent the specific scenario. Follow the general guidelines listed below.

Project Description – Input the Building Address, General Information, Contact Person, and other optional information. Edit the Occupancy to match specific conditions. Occupancy is the only required input.

Fuels / Rates – Edit the cost of fuels and add fuels when necessary. Template projects contain Natural Gas at $1.00 per therm, Electricity at $.10 per kWh and Oil #2 at $1.50 per gallon.

Weather / Defaults – Select the appropriate Daily Weather and Long term Weather Site. Add additional Daily Weather locations or data if necessary. Edit the heating and cooling seasons.

Billing Analysis – Input utility bills and perform billing analysis if applicable.

Spaces – Verify information for entered spaces. Add additional spaces if necessary. If some of the rooms are air conditioned, then rooms that have similar thermostat settings should be aggregated and modeled as a separate space. Ceiling height is set to 8′, adjust if necessary.

Walls / Surfaces – Edit surface description, size and exposure if necessary. Add overhangs on Advanced screen as needed to model exterior shading for windows on this surface. Enter surfaces for any new spaces created in the previous step.

Doors – Edit door description, sizes and number of doors if necessary.

Windows – Edit window description, size and number if necessary.

Infiltration – Input the correct blower door reading. Adjust the ACH to match billing if blower door reading is not applicable. Adjust infiltration of unconditioned space if applicable.

Thermostats – Adjust thermostats to match appropriate temperature set points and schedules. Add cooling if needed. Thermostats have been set at 70F for heating only with no setbacks.

Fans – Adjust CFM or ACH of fan. Delete fan if applicable. Note: TREAT allows one fan per space. Additional fans may be modeled by adding CFM to the existing fan.

Hot Water – Edit or adjust the Hot Water Heater inputs if necessary. Adjust the Number of Occupants Served to match conditions. Add additional fuels under Fuels / Rates if appropriate fuel is not a choice in the Hot Water Heater - Fuel drop down menu.

Lighting – Lighting load in template projects equals 3 Wh/SqFt/Day, which is typical for residential buildings. If you added or removed spaces or changed floor area of any space you need to edit lighting inputs to increase or decrease the lighting load if needed.

Appliances - The template contains typical residential appliances. Add, delete or edit appliances where applicable. Adjust hot water usage or secondary fuels used by appliances if necessary. Match appliance base load to billing where applicable.

Visual Inspection – Template projects contain no recorded Visual Inspections. Add inspections where applicable.

Measurements – Template projects contain no recorded measurements. Record measurements where applicable.

Improvements – Template projects contain no improvements. Use the Improvement Wizard to create the applicable Improvements. Review sample projects to see how various improvements may be modeled.

Packages - Template projects contain no packages. Aggregate Improvements into Improvement Packages to calculate interacted energy savings. Review sample projects to see how various packages may be created.

Check Model Inputs by running the Model Inspector utility by clicking Tools > Model Inspector on the main menu. Review all the warnings and modify model inputs as needed. Run the Model Inspector again to make sure that all errors are corrected.

9.4.1 Sample Project Name: 2 story trued to utility bills.TPG

General Description

This sample project is a two story colonial located in Green Bay, WI. The home contains 1800 square foot of conditioned space heated by an older furnace. The envelope contains no wall insulation, single pane windows and has recorded a blower door reading of 2200 CFM @ 50 Pa. Utility records show a pattern of high energy usage (over 2000 therms/ year for heating). A utility bill analysis has been performed for both electric and natural gas. The furnace and the majority of the ductwork are located in the basement. The home is centrally cooled with a 3 ton split system installed in 1985. The thermostat has been set to 68F as the occupied heating temperature and is set back to 60F for 14 hours per day. The occupied cooling temperature is set to 72F with setbacks to 85F for 12 hours per day.

Hot water is produced by a direct fired, natural gas, 40-gallon hot water heater. Appliances include a clothes washer, electric dryer, electric oven and range, two refrigerators (an older refrigerator is located in the basement).

Improvements include: a high efficiency furnace replacement, a cooling system replacement, air sealing, dense pack cellulose in all exterior walls, addition of 10″ of cellulose in attic over existing fiberglass, refrigerator replacement, window replacement and an full heating system conversion to a high efficiency boiler with an indirect tank for domestic hot water.

A number of Packages have been created to identify savings. These include: (Note: The name of an improvement or package is determined by the user.)

“Insulation & Air Sealing Only” – Dense pack insulation in walls, 10″ additional cellulose insulation in attic, air sealing (reduction from 2200CFM to 1500CFM).

“Savings from Windows Only” – Includes window replacement and infiltration reduction associated with window replacement (estimated 500 CFM reduction)

“All Measures, Furnace option” – Includes a new furnace and all other measures including air sealing, insulation, windows, refrigerator replacement.

“All Measures, Boiler option, no windows” – Include a new boiler, DHW zoned off boiler and all other measures EXCEPT windows.

9.4.2 Sample Project Name: Ranch with Basement.TPG

General Description

This sample project is a ranch with a basement located in Buffalo, NY. This 1200 square foot home employs an older boiler, no wall insulation, single pane windows and has recorded a blower door of 3200 CFM @ 50 Pa. A utility bill analysis has NOT been performed The boiler and all piping is located in the basement. The home employs no cooling system.

The thermostat is set to 65F as the occupied heating temperature and is set back to 60F for 8 hours per day (based upon homeowner interview).

Hot water is produced by a direct fired tank, natural gas, 40-gallon hot water heater. Appliances include a clothes washer, electric dryer, electric oven and range, and an older refrigerator.

Improvements modeled include: boiler replacement, insulation upgrade of walls and attic, refrigerator replacement, compact fluorescent bulbs for lighting, window replacement, and targeted air sealing.

Packages include:

“Insulation and Air Sealing Only” – calculates the savings from dense pack of walls, upgrading attic insulation to R47, targeted air sealing with foam plus infiltration benefits of dense pack (target 1500 CFM).

“Insulation, Air Sealing, New Boiler” – same as above except package has been expanded to also include a boiler replacement.

“All Measures” - Includes insulation, boiler, new refrigerator, window replacement, lighting replacement with compact fluorescent bulbs, and dryer venting to the outdoors (health & safety).

9.4.3 Sample Project Name: Older Style Trailer.TPG

General Description

Sample project is based upon an older style trailer located in Concord, NH. This 890 square foot trailer was built in 1970 and has had a wood frame sloped roof added. It employs the original furnace, minimal wall insulation, single pane windows and has recorded a blower door of 2000 CFM @ 50 Pa. A utility bill analysis has NOT been performed. The trailer employs no cooling system. The thermostat is set to 62F as the occupied heating temperature and is set back to 58F for 12 hours per day (based upon homeowner interview).

Hot water is produced by an electric 30-gallon hot water heater. Appliances include an electric oven, range, and the original 1970 refrigerator.

Improvements modeled include: a high efficiency furnace replacement, air sealing, roof insulation upgrade, new windows, air sealing, a new propane-fired hot water heater and a health & safety improvement named “Flash patch roof”.

Packages include:

“Insulation and Air Sealing Only” –calculates the savings from targeted air sealing and dense packing the roof cavity insulation.

“All Measures”- Includes insulation, new furnace, window replacement, new propane-fired water heater, air sealing and flash patching of the roof (health & safety).

“All Measures Except Windows” – same as above except windows are not included in the package.

9.4.4 Sample Project Name: 6 Unit Garden Apartment.TPG

General Description

Three story garden apartments located in Syracuse, NY. This sample project is a 4300 square foot building containing 6 apartments. The building was constructed in 1965 and contains the original 250,000 btu/hour boiler, R11 insulation in walls, R19 in the attic, double pane windows, and an 80-gallon gas-fired hot water tank. A blower door was not a viable technique to measure infiltration, instead the ACH (air changes per hour) was estimated and adjusted to match billing. The landlord pays all gas bills for heat and hot water and all electric bills. A utility bill analysis has been performed for both electricity and natural gas.

The boiler and the hot water heater are located in the ground level mechanical room. All apartments are cooled by a 12,000 Btu/hour, through-wall unit. These AC units are original circa 1965. The through-wall AC units are estimated to have an aggregated output capacity of 72,000 Btu/ hour.

The thermostat is set to 72F as the occupied heating temperature and not set back (since tenants do not pay for heat). The occupied cooling temperature is set to 75F with setbacks to 90F for 16 hours per day (tenants pay their own cooling costs). Temperature set points were adjusted as part of the comparison to a billing analysis.

Hot water is produced by a direct fired, natural gas, 80-gallon hot water heater. Shared appliances include a coin-op clothes washer with matching coin-op gas dryer. Each apartment has an electric oven and range, a refrigerator, and a dishwasher.

Improvements modeled include: a boiler replacement, an indirect domestic hot water tank zoned off the new boiler, new AC units, targeted air sealing, an additional 10″ of cellulose over the existing 6″ of fiberglass in attic, refrigerator replacement, low flow shower heads, and lighting improvements.

A number of Packages have been created to identify savings.

“New Boiler with Indirect DHW tank, Insulation, Air Sealing” - 93% efficient boiler with outdoor reset control, 28-gallon hot water tank zoned off boiler, 10" of cellulose over existing fiberglass, and targeted air sealing in the attic.

“Electric Measures Only” – Includes measures which reduce electric consumption. This includes new refrigerators, lighting, and air conditioners.

“Boiler and DHW Only” – Includes 93% efficient boiler with outdoor reset control and a 28-gallon hot water tank zoned off the new boiler.

“Insulation & Air Sealing Only” – Increase attic insulation to R52, decrease uncontrolled ACH to 0.64 from 0.81.(estimated 20% reduction based upon visual inspection of large accessible air pathways in attic).

“All Measures” – contains all the Improvements including boiler, DHW tank, windows, AC units, insulation, air sealing, lighting, and refrigerators.

9.4.5 Sample Project Name: 120 Unit High Rise Multifamily.TPG

General Description

A twenty story high rise apartment building located in New York, NY. This sample project is a 78,000 square foot building containing 120 apartments. The building was constructed in 1950 and contains the original 10,000,000 Btu/hour oil-fired steam boiler. The building envelope consists of 8″ block walls with 4″ face brick, 4″ concrete flat roof with no insulation, and single pane windows. Domestic hot water is produced by a separate 500,000 Btu/hr oil-fired boiler with a 500-gallon storage tank. A blower door was not a viable technique to measure infiltration, instead the ACH (air changes per hour) was estimated and adjusted to match billing. The landlord pays all utility costs including oil for heat, hot water and all electric costs. A utility bill analysis has been performed for both electric and #2 oil.

Both boilers are located in the basement level mechanical room. Each apartment contains a through-wall PTAC AC unit installed in the living area. The average AC unit is sized at 12,000 Btu/hour. All AC units were installed in 1982 and are estimated to have an aggregated output capacity of 1,440,000 Btu/ hour (average unit size × 120 units). Note: only ½ of each apartment is served by air conditioning (living area only). Window units are not permitted in bedrooms due to wiring and electrical load concerns.

The thermostat is set to 75F as the occupied heating temperature and not set back (since tenants do not pay for heat -thermostat was adjusted to match billing). The occupied cooling temperature is set to 75F with no setbacks (tenants do not pay their own cooling costs – adjusted to match billing).

Shared appliances include a 6 coin-op clothes washers with 4 matching coin-op electric dryers. These are located in the basement. Each apartment has an electric oven and range, and a refrigerator.

Improvements modeled include: a boiler replacement, new Energy Star refrigerators, new Energy Star rated washers and gas dryers, new AC units, targeted air sealing including window weather stripping, an additional 2″ of rigid insulation under new roof, and lighting improvements.

A number of Packages have been created to identify savings.

“Measures with Payback of 10 years or less” - included measures with a simple payback of ten years or less. Includes: 86% efficient boiler with outdoor reset control, new Energy Star rated refrigerators and clothes washers, gas dryers, window weather strip instead of window replacement, replacement of all incandescent fixtures with 20 W fluorescent fixtures in apartments, and 2″ of additional insulation in roof.

“Fast Payback Package” – Includes measures which enjoy a simple individual payback of 5 years or less. This includes new refrigerators, lighting, window weather stripping, washers, dryers and additional roof insulation.

“All Measures Package” – Contains all measures regardless of simple payback. Package included new boiler, appliances, lighting, roof insulation, new windows, and AC units.