Find a Room’s Ceiling Height

Revit can compute some great info about Rooms – area, perimeter, and volume. But out-of-the-box Revit can’t tell you the height of the ceiling above a room. Fortunately the API lets us find this info. Pulling together some things that have been covered in previous posts, here is the code and a screenshot.

public void RoomCeilingHeight()
    Document doc = this.ActiveUIDocument.Document;
    UIDocument uidoc = new UIDocument(doc);

    // Prompt user to select a room
    Room room = doc.GetElement(uidoc.Selection.PickObject(ObjectType.Element)) as Room;

    // Get the location point of the room.
    // If you want to check other points for a room with non-uniform ceiling height
    // use Room.IsPointInRoom to make sure the points are in the room
    LocationPoint roomPoint = room.Location as LocationPoint;

    // The 3 inputs for ReferenceIntersector are:
    // A filter specifying that only ceilings will be reported
    // A FindReferenceTarget option indicating what types of objects to report
    // A 3d view (see for more info on how this works)
    ReferenceIntersector intersector = new ReferenceIntersector(
        new ElementCategoryFilter(BuiltInCategory.OST_Ceilings),
        (from v in new FilteredElementCollector(doc).OfClass(typeof(View3D)).Cast<View3D>() where v.IsTemplate == false && v.IsPerspective == false select v).First());

    // FindNearest finds the first item hit by the ray
    // XYZ.BasisZ shoots the ray "up"
    ReferenceWithContext rwC = intersector.FindNearest(roomPoint.Point, XYZ.BasisZ);

    // Report the data to the user. This information could also be used to set a "Ceiling Height" instance parameter
    if (rwC == null)
        TaskDialog.Show("Height", "no ceiling found");

10 thoughts on “Find a Room’s Ceiling Height

  1. I have set the ReferenceIntersector.FindReferencesInRevitLinks property true. But it I couldn’t get the proximity to the roofs in the linked documents. Any other options?

  2. Harry.Kindly help me to get intersections from linked documents. I have set the FindReferencesInRevitLinks property as true. I even tried retrieving the 3D view from linked document.I am unable to find help from anyone else. I am waiting or your response.

  3. Hi Harry. It would be necessary to add a limit to the proximity distance in case of multiple levels, so a room on the first floor would not report a ceiling on the second floor.

  4. FindNearest should make sure that it returns the first ceiling found – in your example it should find the first floor ceiling, not the one on the 2nd floor

  5. I’m getting an error The type or namespace name ‘Room’ could not be found (are you missing a using directive or an assembly reference?) (CS0246)

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s