It depends on the application and what the door is made out of.
If you want to block as much sound as possible, you need to use a solid core door.
A solid door is going to block more sound than a hollow one.
If you really want to block as much sound as possible, you’ll want a 5 or 6 inch overlap on each side.
The more overlap you have, the better the it’s going to be acoustically.
Put weather stripping around the perimeter of the door.
If you seal the opening air tight, it’s going to have better acoustical value as well.
It’s probably not as good as a swinging door, but it’s all about the overlap and the seal.
