Every now and then a director will want a character to slam a door as he enters or leaves a room. It can be a very dramatic moment, but too often the entire wall shakes when the door gets slammed. Not good.
Fortunately, there’s an old trick to help prevent this, and it consists simply of having the door flat and the framed door be separate units and not attached to each other.
Here’s the back of the door flat. I’m showing a “Broadway” style flat, although this works with “studio flats” too:
And here’s the self-contained door unit, complete with front molding and a brace:
Here are the two pieces in place:
And here’s a cross-section thru the door and flat, looking down:
All you really need to allow is about a quarter-inch gap, all around, between the framed door and the door flat, including the molding. Depending on the set design and the sight lines, you can have one or two braces on the door unit, secured to the floor with a sandbag or bracket (although of course you don’t want to create any tripping hazards). The wall flats are then braced as they would normally be in your case.
The same idea can be used for a window or any other framed opening. It’s a simple trick and will help keep the audience focused on the story and not get distracted by a shaking wall.