A single layer of brick in a party wall is a moderately good sound insulator. A stud partition wall made of timber and plasterboard is less so. But both can allow enough airborne noise through to be a nuisance. Your solution to the problem depends on the amount of noise coming through: the greater the noise the more you will need to pay to eradicate it completely.
If the problem is a minor one. A heavy duty wallcovering may do the trick. The majority of these materials consist of large.
Tilelike units with a decorative finish. They can be fitted to a wall in the same way as tongueandgroove boarding or plaster board.
An even more effective solution to sound proof walls is more expensive: the insulated false wall. This consists of a stud partition wall separated from the party wall by an airspace and a layer of glass wool blanket which hangs from the ceiling.
To build an insulated false wall, first secure a 100mmsquare lath to the ceiling, parallel to the wall and about 100mm away from it.
Suspend a 75mm glass wool blanket from the lath: secure the blanket by sandwiching it between the lath and a sheet of hardboard or plywood. The blanket should not touch the floor, and there should be an airspace between wall and blanket.
Erect a stud partition wall to seal firmly the glass wool in the existing gap.
It is impossible, using this method. To accommodate switches and wall lights mounted on the existing brickwork — they will be buried when the false wall is built.
Instead, remove these fittings, run the electric cables between the studwork and insulation, and mount the fitting on the new plasterboard wall.