Advanced Energy Settings

After performing an initial energy analysis, you can use the Advanced Energy Settings dialog to specify parameters that affect energy consumption for the building model.

To open the Advanced Energy Settings dialog

  1. Click Analyze tabEnergy Optimization panel (Energy Settings).
  2. In the Energy Settings dialog, for Other Options, click Edit.

The Advanced Energy Settings dialog displays.

Advanced

Export Complexity

Specifies 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, and include surfaces that create a solar obstruction. Simple complexity is used for heating and cooling loads analysis.
  • 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.

Sliver Space Tolerance

Specifies the tolerance for areas that will be considered sliver spaces.

Building Envelope

Specifies the method to use to determine the building envelope.
  • Use Function Parameter. (default) This method uses the Function type parameter of walls, floors, and building pads to determine the building elements considered to be part of the building envelope. If a wall has one adjacent space, analytical surfaces originating from the wall are classified as exterior surfaces. If a wall has two adjacent spaces and its function is Exterior, Foundation, Retaining, or Soffit, analytical surfaces originating from the wall are classified as interior surfaces. If the wall's function is Interior or Core Shaft, analytical surfaces originating from the wall are classified as interior surfaces, regardless of the number of adjacent spaces.
  • Identify Exterior Elements. This method uses a combination of ray-casting and flood-fill algorithms to identify the building elements that are exposed to the outside of the building, the building envelope. Analytical surfaces originating from the building elements in the envelope are classified as exterior or shading surfaces.

Analytical Grid Cell Size

Specifies the cell size for the uniform cubical grid. 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. This parameter is available when Building Envelope is set to Identify Exterior Elements.

Building Service

Specifies the heating and cooling system for the building.

Building Infiltration Class

Specifies an estimate of outdoor air that enters the building through leaks in the building envelope.

Infiltration can be specified as:

  • 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.

Building Data

Insight - Energy Analysis simulates the impact of all of the following parameters across a range. These values affect the BIM setting shown in the Energy Range Factors of Autodesk Insight. Change these parameters only after performing an initial energy analysis.

Building Type

Select the building type that most closely reflects the planned usage of the model. This setting is a default for the entire project.

The building type includes assumptions about the typical schedule of the building based on usage. For instance, a retail store is assumed to be open more hours per year than an office building, and so it uses more energy.

To override the default schedule for the selected building type, use the Building Operating Schedule setting. You can also override the space types for specific spaces.

For assumptions about each building type, see Building Type Data.

Building Operating Schedule

Specify the operating schedule for the building. This setting overrides the default operating schedule, which is based on the selected building type.

This schedule can have a significant impact on the energy results. Choose a schedule that most closely matches the building’s assumed hours of operation.

For assumptions about each building operating schedule, see Building Operating Schedules.

HVAC System

Specify an HVAC system for the project.

For assumptions about each HVAC system type, see HVAC Systems.

Outdoor Air Information

Click Edit to specify the outdoor air per person, outdoor air per area, and infiltration for the whole building.

Room/Space Data

You do not need to add room elements or space elements to the architectural model in order to create an energy model. However, if the architectural model contains rooms or spaces that reside within analytical spaces of the energy model, the Export Category setting determines whether room information or space information is used in the analysis.

Export Category

When this parameter is set to Rooms, Revit passes the Room object name and number to the corresponding Analytical Space name.

When it is set to Spaces, Revit passes the following information for use in the analysis: Space object name and number, Occupancy, Lighting, Equipment, and Zone.

For details, see Space Type Data and Occupancy Schedules.

Material Thermal Properties

Revit offers 3 ways to specify material thermal properties of building elements for energy analysis. These methods can be used in combination with one another to suit different stages in the design process, levels of detail, and user preference.

When you use multiple methods to specify material thermal properties, they are applied in the following order:

  1. Conceptual types are the default.
  2. Schematic types, where enabled, override conceptual types.
  3. Detailed elements, where enabled and where material thermal properties are specified for building elements, override both conceptual types and schematic types.