In the Energy Settings dialog, these settings affect the results of an energy analysis performed using building elements room or space based gbXML export and Revit MEP heating and cooling load calculations.
To open the Energy Settings dialog, click Analyze tab
Energy Analysis panel
(Energy Settings).
The following parameters are listed under the Detailed Model heading.
Export Category
Specify data export for either Rooms or Spaces.
Export Complexity
This parameter applies only to Energy Analysis for Autodesk® Revit® or Export gbXML. Simple complexity is used for heating and cooling loads analysis.
Specify the level of detail provided for openings, and whether shading surface information is exported.
Shading surfaces are surfaces that are not adjacent to any space. They include surfaces that create a solar obstruction.
- Simple. Curtain walls and curtain systems are exported as a single opening (without individual panels). Simple is more appropriate for energy analysis.
- Simple with shading surfaces. Same as simple, but with shading surface information exported.
- Complex. Curtain walls and curtain systems are exported as multiple openings, panel by panel.
- Complex with shading surfaces. Same as complex, but with shading surface information exported. Shading surfaces are not associated with any room/space (roof overhang, free-standing wall).
- Complex with mullions and shading surfaces. Same as complex, but with mullion and shading surface information exported. Mullions in curtain walls are exported as shading surfaces. A simple analytical shading surface is produced from mullions, based on the centerline, thickness, and offset.
Include Thermal Properties
When the Export Category parameter is set to Rooms, select this parameter to include thermal properties in the building energy analysis.
To use this option, the model must include building elements such as walls and floors with assigned element layer material thermal data. If thermal data is not present in the model, the thermal properties default to Conceptual Constructions.
See About Rooms and Spaces for Energy Analysis, About Thermal Properties for Energy Analysis, and Add Thermal Properties to Building Element for Energy Analysis.
Project Phase
Specify the stage of construction.
To analyze the heating and cooling demands of the entire model, the project phase must correspond to the phase for all zones and spaces in the building model. Otherwise, the software analyzes only those zones and spaces with phases that correspond to the project phase.
Sliver Space Tolerance
Specify the tolerance for areas that will be considered sliver spaces. Spaces that are smaller than the specified size are treated as sliver spaces.
See Account for the Volume of Cavities, Shafts, and Chases and Resolve the Volume of Cavities, Shafts, and Chases.
Building Envelope
Specify the method to use to determine the building envelope.
Use Function Parameter This is the legacy option, and also the default. This method uses the Function type parameter of Walls, Floors, and Building Pads to determinate the building elements considered to be part of the building envelope. If a wall has one adjacent space, analytical surfaces originated from the wall will be classified as exterior surfaces. If a wall has two adjacent spaces and its function is Exterior, Foundation, Retaining, or Soffit, analytical surface originated from the wall will be classified as interior surfaces. If the wall's function is Interior or Core Shaft, analytical surface originated from the wall will be classified interior surfaces, regardless of the number of adjacent spaces. See About the Function of Walls, Floors, and Building Pads.
Identify Exterior Elements This method uses a combination of ray-casting and flood-fill algorithms in order to identify the building elements that are exposed to the outside of the building, the building envelope. Analytical surfaces originated from the building elements in the envelope will be classified as exterior or shading surfaces.
Analytical Grid Cell Size
Specify the cell size for the uniform cubical grid used when Building Envelope is set to Identify Exterior Elements. This is the base size of the 3D grid cells, or cubes, used to divide the building shell bounding box into a uniform cubical 3D grid.
Building Service
When the Export Category parameter is set to Spaces, this parameter specifies the heating and cooling systems for the building.
Building Construction
When the Export Category parameter is set to Spaces, this parameter specifies the type of construction, which determines the materials and insulation (U-values) for the building. This information is used for energy analysis, and for heating and cooling loads analysis.
Click in the Value column, and click the Browse button to access the Building Construction dialog. For more information, see About the Building Construction Dialog and Add Thermal Properties to Spaces for Energy Analysis.
Building Infiltration Class
When the Export Category parameter is set to Spaces, this parameter specifies an estimate of outdoor air that enters the building through leaks in the building envelope.
Select one of the following options:
- Loose. 0.076 cfm/sqft for tightly constructed walls.
- Medium. 0.038 cfm/sqft for tightly constructed walls.
- Tight. 0.019 cfm/sqft for tightly constructed walls.
- None. Infiltration is excluded from the calculation of loads.
Export Default Values
When the Export Category parameter is set to Spaces, this parameter determines whether certain default values will be exported.
When it is selected, the default values for People and Electrical Loads, Occupancy, Lighting, and Power Schedules, and building/space type Construction Types are exported together with all user-specified values.
When it is cleared, only user-specified values are exported.
Report Type
When the Export Category parameter is set to Spaces, this parameter specifies the level of information provided in the heating and cooling loads report. Select Simple, Standard, or Detailed.