How to soundproof the shared door?

This wallpaper has a good sound insulation effect, as good as a hotel room. Of course, this matter needs to be discussed with the landlord. Just buy a sticker in the store and stick it on the wall.

2, sealing gap:

Go to the hardware store to buy styrofoam and seal the gap around the window with styrofoam, so that you can't hear the noise when you close the window at night. But if the wall itself is not thick enough, this method will have no effect.

3, nail a layer of wooden wall:

Let the carpenter nail a wooden wall on the wall, arrange the wooden keel first, then take a large piece of plywood and nail the whole wall with nails. Or you can put sound-absorbing cotton (such as glass wool, rock wool, polyester fiber sound-absorbing cotton) in the wooden keel, attach sound-insulating felt and nail plywood, and the sound-insulating effect is also quite good.

4. Sound insulation with sound-absorbing cotton and felt:

First, put some sound-absorbing cotton in the lattice of wooden keel, then stick a sound-insulating felt outside the lattice, and then nail the plywood firmly.