Demolished window - best practice to preserve opening in wall and maintain correct phases in items

[Redrunner92]

In a remodel project a window will be demolished in order to use the opening to allow HVAC ductwork an entrance to the building from a mechanical unit outside. I am wondering what would be BIM-smart way to demolish the window but to preserve the opening in the wall. With just a moment's thought, I came up with these options:

1. Use two families: one for the window itself, the second which is merely a Void which will cut an opening in the wall. This will allow me to mark the window's phase settings appropriately, meaning its creation phase will be "Existing" while the demolished phase will be "New Construction." The opening, meanwhile, will have its creation phase as "Existing" and will have its demolished phase will be set to "None." Benefit: the elements' phase settings will be accurate and an aperture will remain in the wall. Cost: there will be an "Opening" family which is otherwise useless and has the potential to get in the way of other functions of the model. Indeed, upon further thought, the window may not be able to be hosted in the wall atop the Opening family, since the window may not recognize an appropriate host.
2. Use only the one family, being the window, then mark it as demolished in "New Construction." Then split the host wall where the window is, both horizontally and vertically, and mark the wall segment where the window is hosted as demolished in the New Construction phase. Benefit: the window is demolished and its phase settings are accurate, and an opening remains in the wall. Cost: what should be one wall will be segmented into multiple wall elements, which I have found irksome in other projects.

With either approach, I will have to fill in the rest of the wall so it surrounds the ductwork tightly. This is because, as I'm sure many of you would assume, the ductwork's cross-sectional area will be smaller than the existing window's.

Are there other options you have used which work well with phase settings and prevent otherwise-unnecessary splitting of the host wall? I'm glad to hear other approaches and thoughts on the two I listed above.

[barthbradley · Accepted solution]

I would just Phase in a Wall with an Duct-Sized Opening. 

[ToanDN]

- Create a wall based opening family, place it to cut wall under existing phase

- Draw a curtain wall instead of a window to fill the opening, and set the curtain wall type to match the window, also under existing phase

- Demolish the curtain wall

[barthbradley]

[martijn_pater]

I would maybe just cut the infill wall with an in-place void, which would be just about what Bradley is describing there... more or less exactly actually...

[bin]

If the opening is the same size as the existing window, try this:

[Redrunner92]

That seems straightforward, and has the benefit of accounting for the new wall which the contractor will build to match the existing wall. This new wall will have appropriate phase settings, too. Thanks for the suggestion!

[nmcmahonTW94C]

Wow had no idea we could just cut it out.