How can I soundproof an old, unused door?
I couldn’t tell from the picture, but if there’s a gap at the bottom of the door, cover that. Anything from one of those “draft dodger” beanbag things to a rolled up old towel will do the trick. On your side, you can also hang a tapestry or blanket just to muffle the sound transmission a bit. If your roommate is a true friend, you won’t have a problem convincing him to hang something similar. Lastly, if the door’s one of those thin, hollow doors, see if you can get your landlord to offer to replace it with a door of decent weight. Perhaps offering to do the replacement yourself might be sufficient to get the landlord to pay for it. Alternately, if you don’t need to be able to pass through, maybe remove the door from its hinges and replace it with a construction of foam. Check either Home Depot/Lowes/whatever for materials, or perhaps a low department store’s bedding section for a cheap eggcrate. No need to splurge when you’re not even sleeping on it. Mostly though, I think the fabric o
