What happens to my Revit doors in Sefaira?
First, it's helpful to understand what Sefaira does with your Revit model to prepare it for analysis: Sefaira constructs a smart planar model based on the information associated with Revit family instances, specifically geometry and type. For example, Sefaira extracts geometric information from a Revit door family (e.g. it's a tall rectangle), and it extracts type information (i.e. it's a door).
Sefaira constructs the door elements of its smart planar model differently depending on the analysis being considered:
- For energy analysis, doors are discarded and replaced with a wall. This is common practice in energy modeling.
- For daylighting analysis, opaque elements of the door are maintained, but glazing is discarded. This is a shortcoming of our model interpretation capabilities, and can be problematic in situations where primarily glazed doors (e.g. sliding exterior glass doors) are present. We are working to improve our capabilities in this area.
To ensure the Sefaira analytical model expresses your intent, please follow these best practices for managing doors in Revit:
- For energy analysis, you can do one of two things:
- Retain the doors. They will be converted to walls.
- Hide all doors in the Sefaira Energy Analysis view. Not only will this help decrease your overall plane count (helpful when conducting analysis in the plugin), it is also completely acceptable when modeling for energy: the energy analysis won't register door-sized holes in the wall; it will understand only that a wall is in place.
- For daylighting analysis, you should do the following:
- Recognize that any glazing present in the door families will be dropped from the analytical model. This is acceptable for Direct Sun studies (studies that assess only whether or not, but not how much, direct solar radiation reaches the work surface), but may not be acceptable for illuminance calculations like Annual, Date and Time, or Daylight Factor studies.
- Replace any primarily-glazed door families (e.g. sliding glass doors) with window families. This ensures that the VLT you set in the Properties menu will be considered in illuminance calculations. See the "Workaround" section below to learn how to do this.
- Manage doors that are primarily opaque:
- Deleting doors lowers your overall plane count. Since your door is opaque, and Revit replaces it with wall when deleted, the daylighting results will be consistent.
- Retain doors with lites: If you feel it's necessary to assess the impact of small lites within doors, retain your mostly-opaque-doors-with-lites. This will increase plane counts, but will capture the opening in your door (albeit without VLT applied to the lites).
- Hiding doors will result in holes in the wall. This is probably the least applicable approach when considering daylighting performance, unless your door locations (e.g. exit stairways) don't impact the spot performance you are assessing.
If your model contains large solid glass doors, you can do the following to switch them to a window family. Be advised, this will affect any door schedules or tags you may have previously set up. We strongly suggest you only make the following changes in a local copy of your built-for-purpose model.
Then select the Family Category and Parameters icon.
In the dialog that opens, select window from the list (1) then ok (2).
Then, reload the family into the model.
It's up to you if you want to save the family or not, but the changes are saved within the Revit model even if you decide not to change the family. Saving the family just means you could reuse the family on another project without having to repeat this workflow.
Overwrite the existing version and if you had any door tags associated with the door, you might get an additional popup warning you they will be deleted, click Ok to this if you get it.
Now you have a window family which will be treat like all the other windows in your Revit model with regardless to analysis with Sefaira.
If you have any further queries, please contact firstname.lastname@example.org