This section incorporates components from the Component Library (slabs, walls, etc.). All of these components have the following fields:
| Name | An identifier for the design element (i.e. Exterior Wall or Floor Above Garage) |
| Type | Dropdown options referencing a Component Type from the Component Library. Component Types contain energy performance information (i.e. U-value, Equipment efficiency, etc.). Types can be edited and added by clicking the Edit or Add buttons below the Type Dropdown. |
In addition, some design elements can be added and removed by clicking the Add and Remove buttons.
IMPORTANT NOTE: In Ekotrope, ONLY the thermal boundary should be modeled. See examples below:
- For homes with unconditioned basements with insulated framed floors over the basement, ONLY input the framed floor and specify that the location is over an unconditioned basement. Do not input the slab or foundation walls of the basement. If the foundation walls are also insulated, please specify that the Floor is located above an Insulated Unconditioned Basement.
- Even if a space does not have heating or cooling directly serving it, if it falls within the thermal boundary then it should be marked as ‘Conditioned’ in Ekotrope.
- For homes with directly or indirectly conditioned basements or crawl spaces where the primary thermal boundary is the foundation wall and the slab, do not input the framed floor over those spaces. If the foundation walls and slab enclose a conditioned crawlspace please specify Encloses: Conditioned Crawlspace. If they enclose other conditioned spaces such as a basement or living space, please specify Encloses: Conditioned Space. For more information on modeling unconditioned basements please read this article. And for more information on modeling homes with crawlspaces please read this article.
- For homes with directly or indirectly conditioned attics where the attic ceiling/attic exterior is insulated instead of the attic floor, only the attic ceiling/attic exterior should be modeled.
Slab
Foundation slab(s) of the building.
For slabs that are partially above and partially below grade (e.g. walkout basement slabs), split the on-grade section from below-grade section and model as two separate slabs. An on-grade slab becomes a below-grade at an approximate depth of 1’. Thus, when splitting up slabs, make sure the subdividing line is drawn this differentiating depth (of roughly 1’ below-grade).
| Surface Area | Square footage of the slab (or slab section, if multiple) under conditioned space or conditioned crawlspace. |
| Exterior Perimeter | Length, in feet, of the perimeter of the slab (or slab section, if multiple) exposed to ambient ground or air. Only input perimeter of slab area below conditioned space. Include boundary between conditioned space and unconditioned buffer spaces like garages or crawl spaces. |
| Exposed Masonry Area | Square footage of slab not covered by a covering material such as carpet, tile or wood flooring, the R-value of which should be described in Covering R Value. |
| Covering R Value | R-value of carpet or other flooring materials located directly on top of the slab (or slab section, if multiple). Added R value over the masonry slab will reduce heat loss through the slab. Below are R values for some common floor covering materials:
|
| Floor Grade | Slabs that are on grade or down to 1’ below grade shall be described as “On Grade”. Slabs more than 1’ below grade shall be described as “Below Grade”. |
| Encloses | Select the type of space the slab encloses. Options are Conditioned Space or Conditioned Crawlspace. |
Framed Floor
Enter all framed floors that separate conditioned space from unconditioned space, as well as adiabatic floors over other units in multifamily buildings.
| Surface Area | Square footage of the framed floor. |
| Floor is located above | Specify the type of space that the framed floor is located above. |
| Covering R Value | R-value of carpet or other flooring materials located directly on top of the framed floor. Only add R value here if you are not already modeling the floor covering in the assembly layer view. If you have included floor covering as an assembly layer, leave this at 0. Below are R values for some common floor covering materials:
|
Foundation Wall
This section shall include all foundation wall(s) that are part of the primary thermal boundary of the home.
| Height Above Grade | The distance, in feet, the wall extends above grade (measured from the exterior ground level). If the grade varies significantly (for example, in walkout basements), add multiple Basement Walls for the different heights. If the grade only varies slightly, use the average above-grade height of the wall. |
| Depth Below Grade | The distance, in feet, the wall descends below grade (measured from the exterior ground level). If the grade varies significantly (for example, in walkout basements), add multiple Basement Walls for the different depths. If the grade only varies slightly, use the average below-grade depth of the wall. |
| Exterior Perimeter | Perimeter of the basement wall or, if adding multiple Basement Walls for varying grades, the perimeter of that section. |
| Encloses | Select the type of space the foundation wall encloses. Options are Conditioned Space or Conditioned Crawlspace. |
Wall
Above grade walls that separate conditioned and unconditioned space. Include common (adiabatic) walls, exterior walls, garage walls, knee walls, etc. Do not include interior walls within the same unit, garage walls adjacent to the exterior, open crawl space walls adjacent to the exterior, etc.
Note: Common walls should be entered as their own wall entry, with Between Interior and set to Conditioned Space (Adiabatic).
| Surface Area | Total square footage, including fenestration area, of the wall. Measured according to RESNET Standards Appendix A. |
| Surface Color | The tone of the exterior of the wall. Valid inputs are “Light,” “Medium,” “Dark,” and “Reflective.” This input is how we model the solar absorptivity of the wall -- “Dark” walls have highest absorptivity and “Light” walls have lowest absorptivity. For walls where the location is not exposed exterior, this surface color should describe the color of the exterior of the buffer space adjacent to the wall. For example, for walls located between conditioned space and a garage, enter the surface color of the exterior of the garage. If only the reflectance is provided and the material is not transparent or translucent such that no solar radiation can pass through it, you can assume (1 - reflectance = absorptivity). Please verify this with your provider as well. |
| Between Interior and | The type of space located on the exterior of the wall. For example, if wall is next to unconditioned garage select ‘Unconditioned Above Ground Room’. Remember to properly specify common (adiabatic) walls when modeling multifamily housing. |
Rim Joist
Rim joists between two conditioned floors should be entered, but joists that are part of an insulated framed floor or roof should not; thus, do not include floor area of elevated floors extending over unconditioned space. Separate entries are needed for rim joists with different R-values. Typical rim joists have a height of approximately 1’.
Please note that location of rim joists is not a required input because it does not have a significant impact on energy calculations. Most unconditioned spaces are much closer to ambient conditions than indoor conditions.
| Surface Area | Square footage of rim joists located within conditioned space. If the joists are 2x12 members, this is equal to linear feet of perimeter. |
Ceiling / Roof
This section includes both roof assemblies (for vaulted ceilings, conditioned attics, etc.) and ceiling (attic floor)
assemblies. All ceiling / roof modeling is guided by RESNET Standards Appendix A. Only include components that separate conditioned space from unconditioned space or abutting conditioned dwelling units.
| Surface Area | Square footage of roof or attic floor, depending on the location of the thermal boundary. Measured according to RESNET Standards Appendix A. Separate roof entries required for different R-values or different design types (i.e. separate entries for roof assemblies and attic floor assemblies). - For vaulted ceilings, this should be the ceiling area. - For unconditioned attics, this should be the ceiling area below the attic. - For conditioned attics, this should be the attic exterior area above the attic. Do not use the roof pitch multiplier table in this case. |
| Surface Color | The darkness of the exterior of the roof. Valid inputs are “Light,” “Medium,” “Dark,” and “Reflective.” This input is how we model the solar absorptivity of the roof -- “Dark” roofs have highest absorptivity and “Reflective” roofs have lowest absorptivity. If only reflectance is provided and the material is not transparent or translucent such that no solar radiation can pass through it, you can assume (1 - reflectance = absorptivity). Please verify this with your provider as well. |
| Between interior and: | Choose whether this ceiling or roof is the boundary between a conditioned space and an unconditioned attic, a conditioned room, or the outside environment. |
| Attic Exterior Area | For a standard unconditioned attic, the Roof-Deck Area is the roof area between the attic and ambient including any gable walls. If the attic is sealed or vaulted, this field is not important, but we require that it is greater than or equal to Surface Area. Tip: Multiply the attic floor surface area by an appropriate Area Multiplier (you can type equations right into the box). We've included an area multiplier table below for calculating the attic exterior area of a typical roof with different pitches. |
| Clay or Concrete Roof Tiles | Does the roof have clay or concrete tiles? |
The table below shows Area Multipliers assuming a 30 ft (long) by 24 ft (wide) gable end roof. Because our multipliers include the gable ends as roof deck area, these values are slightly higher than roof area multipliers without gable ends. For unconditioned attics, the attic exterior areas generally do not need to be exact measures, so this table should be applicable for most roof geometries. Note: The Area Multiplier should only be used for calculating the Roof-Deck Area of unconditioned attics using the area of the attic floor!
| Roof Pitch | Area Multiplier* |
| 3/12 | 1.13 |
| 4/12 | 1.19 |
| 5/12 | 1.25 |
| 6/12 | 1.32 |
| 7/12 | 1.39 |
| 8/12 | 1.47 |
| 9/12 | 1.55 |
| 10/12 | 1.64 |
| 12/12 | 1.81 |
| 14/12 | 1.94 |
| 16/12 | 2.09 |
| 18/12 | 2.24 |
| 20/12 | 2.39 |
*Use for unconditioned attic roof-decks only.
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