I'm looking to soundproof some interior doors.
My plan was to drill a 1/2" hole at the top and fill it up with foam, but I'm not sure what type of foam to get. I've used tiny foam cans before, but I'm not sure they'd be up for the task. My fear with them is that the first few seconds foam will get stuck to the sides of the door halfway down, and then all of the foam that follows will fall on top of that foam, leaving the bottom portion of the door uninsulated.
I suppose another option (and probably a better one) would be to drill a tiny hole at the bottom, in which a straw from a can of foam would be placed and sealed with silicone. Another hole could be drilled at the top of the door, serving as a vent to get rid of the air that's being displaced by the door.
Anyways, any tips/advice/product recommendations are appreciated.
PS: I will deal with the walls later. More care has to be given to them due to the high risk of fire. Foam puts off gases that are not only flammable, but I believe perhaps also self-oxidizing. I say this because I once knew a guy whose house burned down due to spray foaming the interior walls (during the actual application, not afterwards), and rumor has it that the entire house was engulfed in flames in minutes (too quickly to save a $100k painting) and burned as if it were doused in gasoline.
PSS: The windows are not a concern, as external noises are not typically the problem. IT'S COMING FROM INSIDE THE HOUSE!!! (Obligatory movie quote)