After you have placed room components or space components in all the areas in a plan, you can export your design as a gbXML file and use a third-party load analysis software application to perform a load analysis.
Note: The gbXML file contains all of the heating and cooling information for a project according to the gbXML file structure which is based on a gbXML schema. The gbXML schema was created to help building designers get information about the energy consumption characteristics of their building projects. Refer to
gbXML Schema Support for more information about gbXML elements and attributes that are supported by
Revit. You can also visit
http://www.gbxml.org for more information about the gbXML schema.
To export the design to gbXML
- Click
Export
(gbXML). If asked to turn on the Areas and Volumes setting, click Yes.
Examine the volume in the analytical model
- In the Export gbXML dialog, on the General tab, for Export Category, select Rooms.
- Click the Details tab, and in the right pane, expand the Building Model, levels, and rooms.
Tip: You can right-click a level to expand or select all rooms on the level.
- If warnings display for the building or an item, select the item, and click
(Show Related Warnings) to learn the cause. Then cancel the Export gbXML dialog and correct the problem in the building model. Review and correct warnings until all of the warnings have been resolved throughout the model.
- In the preview of the Export gbXML dialog, zoom in, pan and spin the analytical model to examine the volume for the rooms in the building.
An effective energy analysis can only be performed if the entire volume of the building model is included in exported data. Color should completely fill the volume for all of the rooms in the model. If you detect rooms without fill, cancel the Export gbXML dialog, and resolve the unshaded areas. When areas are too small to place a room, merge the volume for cavities, shafts, and chases with a tangent room.
Note: Sliver spaces display (as shaded) in the analytical model. Sliver spaces do not display in plan or section views.
- On the Details tab, specify energy data as needed.
Examine analytical surfaces
- In the preview of the Export gbXML dialog, on the Details tab, click Analytical Surfaces, and expand the levels and rooms in the building model.
The hierarchy expands to display Roofs, Interior and Exterior Walls, Floors and Slabs, Windows, Doors and Openings. These can be further expanded to display the individual surfaces and openings for a room. See Surface Element for information about surface and opening names.
Tip: You can right-click a level to expand all or select all spaces in the zone.
- In one of the rooms, select a surface type (for example, Interior Walls), and click
(Isolate). You can also select individual surfaces from within the surface type folder for a room.
- Zoom in, pan, and spin the analytical model as needed to examine all surfaces in the model, checking to be sure that each surface is correctly identified.
If you detect surfaces that are incorrectly identified, you must cancel the gbXML Export dialog, and fix the problem in the building model.
- If you are satisfied with the integrity of the analytical model, click Next.
- In the Export gbXML dialog, navigate to a folder where you want to save the gbXML file.
- Enter a name for the gbXML file, and click Save.
To export the design to gbXML
- Click Export(gbXML).
If asked to turn on the Areas and Volumes setting, click Yes.
Examine the volume in the analytical model
- In the Export gbXML dialog, on the General tab, for Export Category, select Spaces.
- Click the Details tab. and on the right pane, expand the Building Model, zones, and spaces.
Tip: You can right-click a zone to expand or select all spaces in the zone.
- If warnings display for the building or an item, select the item, and click (Show Related Warnings) to learn the cause. Then cancel the Export gbXML dialog and correct the problem in the building model. Review and correct warnings until all of the warnings have been resolved throughout the model.
- In the preview of the Export gbXML dialog, zoom in, pan and spin the analytical model to examine the volume for the spaces in the building.
An effective energy analysis can only be performed if the entire volume of the building model is included in load calculations. Color should completely fill the volume for all of the spaces in the model. If you detect spaces without fill, you should cancel the Export gbXML dialog, and place or modify spaces to resolve the unshaded areas. When areas are too small to place a space, merge the volume for cavities, shafts, and chases with a tangent space.
Note: Sliver spaces and the zones associated with sliver spaces display (as shaded) in the analytical model. Sliver spaces do not display in plan or section views.
- On the Details tab, specify energy data as needed.
See Specifying Energy Analysis (gbXML) Settings for parameter definitions.
Examine analytical surfaces
- In the preview of the Export gbXML dialog, on the Details tab, click Analytical Surfaces, and expand the zones and spaces in the building model.
The hierarchy expands to display Roofs, Interior and Exterior Walls, Floors and Slabs, Windows, Doors and Openings. These can be further expanded to display the individual surfaces and openings for a space. See Surface Element for information about surface and opening names.
Tip: You can right-click a zone to expand all or select all spaces in the zone.
- In one of the spaces, select a surface type (for example, Interior Walls), and click (Isolate).
You can also select individual surfaces from within the surface type folder for a space.
- Zoom in, pan, and spin the analytical model as needed to examine all surfaces in the model, checking to be sure that each surface is correctly identified.
If you detect surfaces that are incorrectly identified, you must cancel the gbXML Export dialog, and fix the problem in the building model.
- If you are satisfied with the integrity of the analytical model, click Next.
- In the Export gbXML dialog, navigate to a folder where you want to save the gbXML file.
- Enter a name for the gbXML file, and click Save.