Calculate Total Building Envelope

I’d like to figure out a way to calculate the total building envelope.

For example, in Revit you can create a schedule that looks at exterior walls and calculate the total area. This assumes that wall types have their function set to exterior, and ideally, any below grade walls are either filtered by level, or set to something other than exterior. However, the wall area reports actual area (so it excludes window/door openings). Now, while it might be possible to create a window or door schedule to calculate the total area of those elements then add to the wall area, it might become problematic if there are interior windows or other elements that might produce and inaccurate calculation and require additional methods of filtering.

Ideally, there is a way to calculate the total exterior envelope inclusive of fenestration. This would be beneficial for ComCheck energy calculations which require the total wall area and then an input for the fenestration which ComCheck then subtracts the area from the associated wall.

Here’s where I would also like to take it a step further. For quantity take-offs and estimating, I would like a way to determine the total wall area of specific wall types/materials inclusive of the fenestration. Seems like I would need a way to associate a specific window opening (and its area) to the wall it is cutting. The wall types’ ‘total’ area inclusive of fenestration would be used for the materials quantity and associated waste factor. Or is there just a way within Dynamo to extract the wall area including cut opening penetrations? Building area plans have a way to identify “exterior walls” is there a way utilize this some way? Maybe there is a way to copy all exterior walls so that openings are excluded and paste as a new object for an envelope calculation?

Ideally this works on linked Revit models, but if it can only happen in the model directly that can be worked around as well.

It is possible to calculated it If there are marks or parameters to detect walls to be calculated.
And there can be several ways to achieve the mission.
for example, If your walls are all rectangular, it can be easily calculated by length*height, so all hosted doors,and windows will be ignored.
If not all walls are rectangular, you need to use some geometricla methods to do it, but still possible.

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hello, it may be possible to base yourself on the surface of the floors by removing balconies and loggias and by extruding the surface between respective levels (a track may be to be exploited)

My old ‘exterior’ room trick works wonders here.

  1. Create a set of room separation lines just outside of the property line on every level of the building, and place a room just inside the outside edge. This room will automatically be bound by those boundary lines and the exterior walls.
  2. Get the geometry of the room, which will be a donut shape of sorts.
  3. Pull the room boundaries to get the walls which bound the room. Get the geometry of each (this is problematic for curtain walls, but you hadn’t mentioned these, and they’re a bit easier OOTB as you can sum the area of all their panels), and intersect with the geometry of the room. This will get you a surface with a bunch of openings in it. Reporting the area of these will give you the functional area of each wall, including corner conditions, but omitting the area of each window and door.
  4. Get the curve loops of each surface, and patch them into a surface. For each set of curve loops, get the one with the largest area. This is the area of the exterior wall surface omitting all the window/door openings.
  5. Group each of the area types (with and without windows) by the host element (as walls can bound a room on multiple levels). Sum the groups, and write the two values to each wall.