Making a Soundproof Door
I am a fairly skilled carpenter, and am just starting to build a house in southern Mexico (where I live). I want to make the bathroom as quiet (on the outside) as possible. The walls are going to be a panel of concrete and pulyurathane combined (5″ thick) and so I think the door is the weak spot. I am wondering if I make a door with the two faces from thick (1/2″) plywood or MDF, brace them internally on a system of ribs that only are attached to one face interspersed with ribs on the other face (but not touching except at the rim) would give a substanially noise-reduced door. Any ideas out there?
There is some merit to what you propose (though it would be fairly heavy, with two sheets of 1/2" plywood). What you need is a combination of stiffness, mass, damping, and isolation.
From an acoustics standpont it would be wise to make the two faces different with weight/stiffness (eg, one 1/2" and one 3/8") so that they don't resonate at the same frequency.
It would also be wise to somehow introduce some damping, but I haven't got a good idea for that. Perhaps put some sort of soft rubber between the plywood and your ribs ...
It would be nice to somehow isolate the two sides around the edge, perhaps with some sort of rubber section between.
(And, of course, there are no doubt sound-damping doors for sale commercially. But what fun is that?)
Split the jambs at the outer edge of the stops, sound damper in between.
If for the CIA, 2 doors-offset and at an angle to each other.