To soundproof a room, insulate and caulk outlet boxes, add weatherstripping to doors and windows, and repair cracks in the room's walls. Fill in gaps between the floorboards, and install storm windows.
- Insulate and caulk outlet boxes
Turn off the electricity to the room. Remove the face plates from the outlet boxes and light switches. Cover each box with a foam insulator designed for electrical boxes. Reattach the face plates. Apply white painter's caulk around the edges of the face plates.
- Add weatherstripping to windows
Wash and dry the edges of the windows. Cut adhesive-backed weatherstripping to the length needed for one edge of the window. Remove the backing paper, and press the strips into place. Weatherstrip all of the windows' edges.
- Place weatherstripping under doors
Install twin-fin silicone door sweeps at the bottom of the doors. Choose sweeps designed for the type of doors in the room.
- Repair drywall cracks
Fill any cracks in the walls with white painter's caulk. Paint the caulk to match the walls.
- Fill gaps between floorboards
If you have older hardwood floors, fill in gaps between the boards with wood filler. Sand the wood filler until smooth.
- Install storm windows
Install storm windows that are designed to reduce sound flow. Leave a large area between the regular windows and the storm windows to increase the sound insulation.