Alternatives
Located on the project summary screen, the Alternatives feature allows you to perform comparisons of different variations of a building within the same project.
These variations include:
The purpose of the Alternatives section is to compare the impact that various building construction materials have on the output. To do this, create a linked alternative, unlink the Templates section to allow modifications, then compare the output of each alternative to determine the best construction materials. The maximum number of alternatives is dependent upon the size of the file. Each alternative will have common functions. The dropdown from the Navigation Bar is used to display information for a particular alternative.
Collapse Alternative
Alternatives can be hidden to minimize the space taken up per alternative on the screen.
Make Baseline Alternative
The alternative in the first position is always the baseline used for energy and economic comparison. An alternative can be made the baseline by using this feature. Linked alternatives will be updated to reflect their source alternative when reordered. This symbol is not displayed in the first alternative.
● For example – Alternative 3 is linked to Alternative 1. However, Alternative 2 is made baseline, shifting Alternative 1 to Alternative 2’s spot. Alternative 3 is updated to reflect that it’s linked to Alternative 2.
Add Linked Alternative
An additional alternative can be created by linking to another alternative. Use the Add Linked Alternative button to create the new alternative. Each subsection (e.g. Templates, Weather, Building & Site, Systems, etc.) is linked to the source alternative. The link can be broken by using the corresponding section menu and changing the relationship from link to copy.
Delete Alternative
An alternative can be deleted by clicking the delete icon. Alternatives that are providing content to others via the link feature cannot be deleted. Subsequent alternatives are renumbered to reflect the reduction in alternative count.
● For example – In a file with 5 alternatives, Alternative 3 is deleted, Alternative 4 becomes Alternative 3, and Alternative 5 becomes Alternative 4.
Change Order of Alternative
Any alternative that is not the baseline alternative can be reordered amongst the project alternatives. "Grab" the alternative level gripper to move the desired alternative to the right or left within the summary screen. As the alternative is moved, the destination location is highlighted. As alternatives are moved, the Alternative number is updated automatically.
Alternative Name
An alternative maybe renamed from the default name given by the program at time of alternative creation by selecting and then typing in the box. The default name of the first alternative is “Primary” and subsequent alternatives’ names depend upon that which they are sourced from.
Results Ribbon
The results ribbon displays a summary of the calculation results for the Base Alternative. For subsequent alterative within the project, it provides a view of how the alternative compares to the Base Alternative.
Jump to Reports 
The Jump to Reports Button open the Reports subsection where reports may be selected for viewing or export.
Last Simulation Method
The Last Simulation Method section shows the time at which the last simulation was performed, and the type of simulation that was run.
Jump to Calculate Results 
The Jump to Calculate Results button opens the Calculate Results subsection. It automatically marks the alternative from which it was clicked for calculation.
Section Specific Controls
Templates
The templates section shows which theme is being used and how many templates have been created. Click on the Jump to Template button to navigate to the Templates section of TRACE® 3D Plus. A linked alternative may have templates added but the theme will be the same as that of the first alternative created within the project.
Theme
The theme that was selected at the time of project creation is displayed here. All alternatives within a project use the same theme, it cannot be modified.
Number of Templates
The sum of Building Construction, Room Construction, Internal Load, Ventilation, Room Types and Zone Type templates included in the alternative.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Templates Validation Errors icon to view errors applicable to this subsection.
Linked Icon 
The linked icon within the Templates section denotes that templates are linked to another alternative. When it is orange, this signifies that the Template subsection is linked to another alternative. When linked, no changes can be made within the linked alternative and entry to a linked alternative’s Templates section will result in a message with a link to go to the source alternative to view/modify templates.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Templates
Create New Templates creates an entirely new section within the alternative. When Create New is used from the Templates Section, the templates from the theme that was selected at the time of project creation are brought into that alternative. A new theme may not be used within alternatives contained in one project file.
Copy Templates From
Copy Templates From creates a section that is a copy of data in the source alternative at the time the copy is created. As sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative.
Link Templates To
Link Templates To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Changes in the source alternative are propagated to the linked alternative and the linked alternative cannot be viewed when a linked section is entered. A previously linked alternative may not be used as the source data for a linked alternative, thus is not displayed as an option.
Unlink Templates
Unlink breaks the link to the source alternative, making a copy of the source data which may now be modified from the alternative itself.
Comments
The comments entry area is used to add comments about a section within an alternative
Jump to Subsection 
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered.
Input Considerations
Templates and Building & Site have a unique relationship in that when one is linked but not the other, behavior depends upon the linked sections and alternative that they are sourced from. When the building section is linked but the templates are not linked (they have been unlinked since the time the section was created) no templates may be deleted or renamed from the linked alternative, including room types. Templates inputs can only be modified.
If the templates have been unlinked, but the building is still linked, any room types added to the source alternative that have rooms assigned to them will be propagated to the linked alternative. When a room type is added to a theme, a new building construction template is brought in with the name “Using Building Construction Template #00n”. Therefore changes made to the General Building Construction template are not applied to these rooms. To apply the same construction template, change it to match the rest of the templates used in Room Types.
Weather
The weather section shows the selected location and design weather. Click on the Jump to Weather button to navigate to the Weather subsection of the Site and Building section of TRACE 3D PLUS. Different weather locations may be used for alternatives within the same project file. See Weather Library.
Location
The location of the weather file is displayed along with the type of weather file used. For a new alternative, this comes from the Project Defaults.
Design Weather
The design weather conditions are displayed here.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Weather Validation Errors icon to view errors applicable to this subsection.
Linked Icon
The linked icon within the Weather section denotes that Weather is linked to another alternative. When it is orange, this signifies that the Weather subsection is linked to another alternative. When linked, no changes can be made within the linked alternative and entry to a linked alternative’s Weather section will result in a message with a link to go to the source alternative to view/modify the weather.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Weather
This option creates an entirely new section within the alternative. When Create New is used from the Weather Section, the weather from the Project Preferences that was selected at the time of project creation are brought into that alternative.
Copy Weather From
Copy Weather From creates a section that is a copy of data in the source alternative at the time the copy is created. A sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative.
Link Weather To
Link Weather To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Changes in the source alternative are propagated to the linked alternative and the linked alternative cannot be viewed when a linked section is entered. A previously linked alternative may not be used as the source data for a linked alternative, thus is not displayed as an option.
Unlink Weather
Unlink breaks the link to the source alternative, making a copy of the source data which may now be modified from the alternative itself.
Comments
The comments entry area is used to add comments about a section within an alternative.
Jump to Subsection
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered.
Input Considerations
It may be desirable to compare different weather if a building’s location could impact the cost to operate it.
Building & Site
The Building & Site section shows a building summary, including the number of rooms, zones, and gross and conditioned floor areas. Click on the Jump to Create Building button to navigate to the Create Building subsection within the Site and Building section of TRACE 3D Plus.
Rooms
The number of rooms in the building as well as the number assigned to zones are displayed here. It provides a way to quickly see whether all rooms have been assigned to zones.
Zones
The number of zones in the building as well as the number of zones with rooms assigned to them. It provides a way to quickly see whether all rooms have been assigned to zones as well as whether there are any empty zones.
Gross Floor Area
The total floor area of the building is displayed in this section. This is the area of floor space from center to center of wall that enclose each space. All areas within the building are reported here.
Conditioned Floor Area
The total conditioned floor area does not include spaces that are assigned to the Unconditioned Spaces category within Create Zones.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Building & Site Validation Errors icon to view errors applicable to this subsection. Validation errors are displayed as either a red or yellow minus (-) sign. Red errors prevent the file from being calculated. Yellow warnings are just that, notifications that there are potential conflicts with program inputs. Click on the icon to view the errors and/or warnings so they can be addressed.
Linked Icon
The linked icon within the Building & Site section denotes that the building and site data are linked to another alternative. When it is orange, this signifies that the Building & Site subsection is linked to another alternative. When linked, no changes can be made within the linked alternative’s Create Building or Create Site subsections; entry to those subsections will result in a message with a link to go to the source alternative to view/modify.
The Create Zones section may be entered regardless of linked state as assignments are never linked.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Building & Site
Create New Building & Site creates an entirely new section within the alternative. When Create New is used from the Building & Site Section, the existing data in that alternative are deleted, including all rooms and assignments to zones. There will be one zone left in the building, as there is when a new building is created. Building & Site cannot be deleted from an alternative that provides source data to a linked alternative.
Copy Building & Site From
Copy From creates a section that is a copy of data in the source alternative at the time the copy is created. As sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative.
Link Building & Site To
Link Building & Site To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Changes in the source alternative are propagated to the linked alternative and the linked alternative cannot be viewed when a linked section is entered. A previously linked alternative may not be used as the source data for a linked alternative, thus is not displayed as an option.
Unlink Building & Site
Unlink breaks the link to the source alternative, making a copy of the source data which may now be modified from the alternative itself.
Comments
The comments entry area is used to add comments about a section within an alternative.
Jump to Subsection
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered. When Building & Site is linked to another alternative, Create Zones can be modified in the linked alternative.
Input Consideration
Building & Site and Templates have a unique relationship in that when one is linked but not the other, behavior depends upon the linked sections and alternative that they are sourced from.
For example, if the building is linked to one alternative and templates to another alternative, the room type in the alternative that sources the building data may not include the room types used in the linked alternative, thus the second alternative’s rooms would be of the default room type from the templates used in that alternative. Therefore, additional room types added to the building source alternative, even though templates are no longer linked, are propagated based on the building section being linked.
Any alternative that sources Building Data to a linked alternative must propagate additions to Room types to the linked alternative, even if Templates are not linked. To understand what this is, consider the following thought experiment:
For example: Assume a linked copy is made of Alternative 1, and Templates are unlinked in Alternative 2. When a Room Type is added to Alternative 1, and a room is created and assigned to it, Alternative 2 would not have that room type to assign to the room that propagates to it based on the building link. Therefore, Room Types added to an alternative that provides source Building Data to another will be propagated to that linked Alternatives Templates section, even though it is not formally linked.
Similarly, deletions/renaming of templates in an Alternative with only Building linked is not allowed, because they exist in the source alternative.
Even with Building & Site linked, Create Zones can be accessed and modified in a linked alternative and room assignment/zoning changes are not propagated to a linked alternative from the source.
Rooms added to a source alternative are propagated to any alternatives with Building & Site linked, however, they are not assigned to zones in the linked building, this must be done manually. Rooms deleted from a source alternative will be removed from a linked building and those rooms are removed from zone assignments. If the zone to which the room had been assigned becomes empty, it must be manually deleted from Create Zones.
Downstream assignments impacted by changes to Zoning must be reviewed – additional zones must be manually assigned to a system.
Systems
The Systems section shows a summary of the airside system that have been created including the number of systems and the number of assigned and total zones. Click on this section to navigate to the Systems section of TRACE 3D Plus. See Systems Library.
Systems
The number of systems in the building are listed here.
Zones
The total number of zones and count of assigned zones are listed here. It provides a way to quickly see whether all zones have been assigned to systems.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Systems Validation Errors icon to view errors applicable to this subsection. Validation errors are displayed as either a red or yellow minus (-) sign. Red errors prevent the file from being calculated. Yellow warnings are just that, notifications that there are potential conflicts with program inputs. Click on the icon to view the errors and/or warnings so they can be addressed.
Linked Icon
The linked icon within the Systems section denotes that Systems are linked to another alternative. When it is orange, this signifies that the Systems section is linked to another alternative. When linked, no changes can be made within the linked alternative’s Select Systems or Configure Systems subsections; entry to those subsections will result in a message with a link to go to the source alternative to view/modify.
The Assign Zones section may be entered regardless of linked state as assignments themselves are never linked.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Systems
Create New Systems creates an entirely new section within the alternative. When Create New is used from the Systems section, all systems are deleted from the alternative and any zones that had been assigned to that system are unassigned. The Systems summary section will reflect that there are no assignable zones until a new system is added.
Copy Systems From
Copy Systems From creates a section that is a copy of data in the source alternative at the time the copy is created. As sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative. Where possible, zone assignments are carried forward in the copied alternative as well.
Link Systems To
Link Systems To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Changes in the source alternative are propagated to the linked alternative and the linked alternative cannot be viewed when a linked section is entered. A previously linked alternative may not be used as the source data for a linked alternative, thus is not displayed as an option.
Where possible, zone assignments are carried forward in the copied alternative as well but zone assignments can be edited within the linked alternative.
Unlink Systems
Unlink breaks the link to the source alternative, making a copy of the source data which may now be modified from the alternative itself.
Comments
The comments entry area is used to add comments about a section within an alternative.
Jump to Subsection
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered. When Systems is linked to another alternative, Assign Zones can be modified in the linked alternative.
Input Considerations
Even with Systems linked, the Assign Zones subsection of Systems is accessible. Any zones that weren’t assigned in the source alternative, will not be assigned to a system in a linked alternative nor will zones that have been created in the linked alternative.
When Building and Systems are both linked, the zone assignments are copied from the source alternative.
Zone Equipment is never linked when Systems is linked to another alternative. When Systems section is linked or copied, the zone equipment is copied at the time of link or copy. When changes to Zone Equipment via Zone Groups creates new coils for plant assignment, these coils are unassigned and must be assigned manually.
DOAS cannot be modified from a linked system.
Plants
The plants section shows the number of cooling plants, heating plants, loops, and number of assigned and total systems. Click this section to navigate to the Plants section of TRACE 3D Plus. See Plant Configurations Library.
Loops
The number of loops and assignable loops are listed.
Systems
The total number of systems and count of assigned systems are listed here. It provides a way to quickly see whether all assignable systems have been assigned to plants. Unitary (DX) equipment doesn’t require a plant, with the exception of VRF and WSHP systems.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Plants Validation Errors icon to view errors applicable to this subsection. Validation errors are displayed as either a red or yellow minus (-) sign. Red errors prevent the file from being calculated. Yellow warnings are just that, notifications that there are potential conflicts with program inputs. Click on the icon to view the errors and/or warnings so they can be addressed.
Linked Icon
The linked icon within the Plants section tells denotes Plants are linked to another alternative. When it is orange, this signifies that the Plants section is linked to another alternative.
When linked, no changes can be made within the linked alternative’s Select Plants and Configure Plants subsections; entry to those subsections will result in a message with a link to go to the source alternative to view/modify.
The Assign Systems and Assign Loops sections may be entered regardless of linked state as assignments themselves are never linked.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Plants
Create New Plants creates an entirely new section within the alternative. When Create New is used from the Plants Section, all plant equipment is deleted from the alternative and any systems that had been assigned to those plants are unassigned. The Plants summary section will reflect that there are no assignable systems until a new plant is added, for systems that require plant equipment.
Copy Plants From
Copy From creates a section that is a copy of data in the source alternative at the time the copy is created. As sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative.
Link Plants To
Link Plants To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Changes in the source alternative are propagated to the linked alternative and the linked alternative cannot be viewed when a linked section is entered. A previously linked alternative may not be used as the source data for a linked alternative, thus is not displayed as an option.
Unlink Plants
Unlink breaks the link to the source alternative, making a copy of the source data which may now be modified from the alternative itself.
Comments
The comments entry area is used to add comments about a section within an alternative
Jump to Subsection
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered. When Plants is linked to another alternative, Assign Systems can be modified in the linked alternative.
Input Considerations
Even with Plants linked, the Assign Systems subsection of Plants is accessible and may be modified. Any systems that weren’t assigned in the source alternative, will not be assigned to a system in a linked alternative. If a linked alternative contains a system that didn’t exist in the source, it must be manually assigned to a plant in the linked alternative.
When Systems and Plants are both linked, the system assignments are copied from the source alternative.
Zone Equipment is never linked when Systems is linked to another alternative. When Systems section is linked or copied, the zone equipment is copied at the time of link or copy. When changes to Zone Equipment via Zone Groups creates new coils for plant assignment, these coils are unassigned and must be assigned manually.
Economics
The economics section shows the number of utility rates assigned to the alternative. The investment cost and operation, maintenance, and repair (OM&R) costs are also displayed. Click on this section to navigate to the economics portion of TRACE 3D Plus.
Utilities
The number of utility rate structures used in the alternative is listed here.
Investment Costs
The total of investment costs for the alternative is displayed.
OM&R Costs
The total Operations, Maintenance and Repair costs is displayed.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Economics Validation Errors icon to view errors applicable to this subsection. Validation errors are displayed as either a red or yellow minus (-) sign. Red errors prevent the file from being calculated. Yellow warnings are just that, notifications that there are potential conflicts with program inputs. Click on the icon to view the errors and/or warnings so they can be addressed.
Linked Icon
The linked icon within the Economics section denotes that Economics is linked to another alternative. When it is orange, this signifies that the Economics section is linked to another alternative. When linked, no changes can be made within the linked alternative’s Utilities or Costs subsections, and will result in a message with a link to go to the source alternative to view/modify Utility Rates.
Meters and Lifecycle Parameters subsections may be entered regardless of linked state as assignments are never linked. The Meters page is used to assign meters to utility rates in the linked state. Lifecycle Parameters are common to all alternatives in the project, thus changes to one alternative always impacts all alternatives.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Economics
Create New Economics creates an entirely new section within the alternative. When Create New is used from the Economics Section, the default utility rate from Project Preferences is added to the alternative and the Life Cycle Parameters are restored to default values. All meters, meter assignments and costs are destroyed.
Copy Economics From
Copy From creates a section that is a copy of data in the source alternative at the time the copy is created. As sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative.
Link Economics To
Link Economics To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Utility rates from the source alternative replace those that were in the alternative. Default Building Meters are created to match based on the end use consumed in the linked alternative. Custom Meters are copied as well, if the fuel type is consumed in the linked alternative, and if end uses assigned to those meters exist in the linked alternative, they are copied as well.
Jump to Subsection
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered. When Economics is linked to another alternative, changes cannot be made from the Utilities Subsection.
Input Considerations
The Utilities subsection of Economics cannot be accessed in a linked alternative. Change to the utility rate structure must be made from the source alternative. When a linked alternative has end uses that did not exist in the source, the program will create the Default Building Meters and assign to the utility rate structure if a tariff exists for that fuel type.
Custom Meters will be created in a linked alternative if the fuel type is consumed in the project alternative and the end use assignments will be copied if the end use exists in the linked alternative.
Assignment of Meters to Utility Rate structures can only be performed from the Meters subsection of Economics within a linked alternative. Select the meter in the tree and assign to utility rate using the dropdown menu in the upper left. If a utility rate doesn’t include a tariff for the selected fuel type consumed by the selected meter, it will not be displayed and must be added from the Utilities tab of the source alternative.
Lifecycle Parameters are common to all alternatives and can be changed from any alternative regardless of linked status.
Costs cannot be modified in a linked alternative.
Simulation Settings
The simulation settings section shows the simulation time step and simulation methodology. Click on this section to navigate to the simulation settings portion of the project summary section of TRACE 3D Plus.
Time Step
The simulation timestep for the alternative is displayed.
Simulation Method
The simulation method for the alternative is displayed.
Show Validation Errors
In order to view errors found prior to calculating a file, click on the Show Simulation Settings Validation Errors icon to view errors applicable to this subsection. Validation errors are displayed as either a red or yellow minus (-) sign. Red errors prevent the file from being calculated. Yellow warnings are just that, notifications that there are potential conflicts with program inputs. Click on the icon to view the errors and/or warnings so they can be addressed.
Linked Icon
The linked icon within the Simulation Settings section denotes that Simulation Settings are linked to another alternative. When it is orange, this signifies that the Simulation Settings section is linked to another alternative. When linked, no changes can be made within the linked alternative and entry to a linked alternative’s Simulation Settings section will result in a message with a link to go to the source alternative to view/modify the settings.
Linked Dropdown Menu
The dropdown menu provides actions that can be taken on the section from which it is selected. The options available depend upon whether the section is a copy of an existing alternative.
Create New Simulation Settings
Create New Simulation Settings creates an entirely new section within the alternative. When Create New is used from the Simulation Settings section, the default Holiday Calendar, Simulation Method, Time Step and Calculation Algorithm form Project Defaults are used. The remainder of General Settings, Load Design and Energy Simulation Parameters are set to program defaults.
Copy Simulation Settings From
Copy From creates a section that is a copy of data in the source alternative at the time the copy is created. As sub menu is shown which is used to select the alternative’s source data to be copied. Changes in the source alternative have no effect on the copied alternative.
Link Simulation Settings To
Link Simulation Settings To creates a section that references data from the source alternative. A sub menu is shown which is used to select the alternative that will provide the source data. Changes in the source alternative are propagated to the linked alternative and the linked alternative cannot be viewed when a
Jump to Subsection
When this button is used, the section within the alternative from which it was clicked from the project summary screen is entered. When Simulation Settings are linked to another alternative, changes cannot be made from the Simulation Settings screen when a linked alternative is selected from the Alternatives Dropdown menu.
Input Considerations
Using a different simulation timestep might be used to reduce the time it takes to run a model or to compare the difference is results when using a different methodology.