How Cavity Closure works

Written by László Nagy

This Tech Note will try to explain how the Cavity Closure feature of Windows/Doors works and what each of it parameters control.
First of all, Cavity Closure usage makes sense with Composite Walls, where there are at least 2 or more skins. First, you have 3 choices besides 'None" for Cavity Close. These are:

1. Turn in: skins will be turned on the side you clicked when you created the Window/Door.
2. Turn out: skins will be turned on the side opposite the side you clicked when you created the Window/Door.
3. Continuous: the two outermost skins on the two sides of the Composite structure will be joined on the sides of the Window/Door.

The next parameter is Cavity Side. You may specify 'Both', 'Left', 'Right' to determine on which side(s) of the Window/Door Cavity Closures should be created.
No. of skins to turn: 1 or 2 can be chosen in ArchiCAD 8.1. (In ArchiCAD 8, 0 could be chosen as well, but it is illogical - why would you use Cavity Closure if you don't turn any skins - so it was omitted). Here, if 1 skin is turned, it will be turned with its outside surface aligning the sides of the Window/Door. If 2 skins are turned, the inside surface of the outer skin will be aligned with the sides of the Window/Door. This means it will overlap the end of the Window/Door, so the frame width of the Window/Door must be set accordingly to be a larger value.
If 'Joint' is ON, a small joint will be placed at the end side of the innermost turned skin. The next two parameters will specify the Fill Pattern Pen Color and Fill Type of the Joint (Joint Pen was not available in ArchiCAD 8).
You have to consider the Placement Method of the Window/Door as well when using Cavity Closures. If you use the 'Edge' Placement Method, you will not see the outermost skin turned when 2 skins are turned, as there is no room for it to turn. When you use the 'Reveal' Placement Method, you need to know that both the Reveal and Cavity Closure are drawn, which can bring strange results. So it is not recommended to use Reveal in connection with Cavity Closure. The best choice is to use the 'Sill' Placement method.

Page last updated: Saturday, December 19, 2009