Chapter 9: Sound


Sound can travel between the new loft conversion and the rest of the house, and if you have a semi-detached or terraced house, it can also travel through your neighbours’ walls without soundproofing.

If your loft is going to be used for music lessons or DIY, for example, your neighbours will thank you if you fit soundproofing, as will the rest of your house!


Sound waves can either be reflected, transmitted or absorbed by different surfaces and the idea of soundproofing, of course, is to absorb any noise. It’s not just about keeping any noise you make to a minimum, however. Soundproofing also benefits you by cutting down on outside noises such as your neighbour’s love of heavy rock at 3am, the noise of trucks rumbling past or the not so distant motorway.

Sound can travel from the loft to the floors below by airborne transfer and impact transfer.

To prevent airborne transfer, the loft structure should be airtight; sealant should be used under skirting boards, floorboards and edges, and insulation should be taped.

To stop impact transfer, high-density cement-infused chipboard can be added and the spaces between floor joists can be filled with 100mm of sound deadening quilt and in the partitions around the loft.

Soundproofing isn’t a huge job but it should still be fitted by a professional.

Passive Absorption

Passive noise control basically means using methods that suppress the sound by modifying the room.

The addition of stud walls does slightly reduce the size of the room, but it also allows for a gap of around an inch between the stud wall and the existing wall, so soundproofing can be fitted. Materials can include mineral wool and acoustic foam among others.

There does need to be a clear gap between the stud wall and the existing wall, and no part of either wall should touch the other to ensure maximum soundproofing. Fitting non-porous soundproofing barriers, such as plasterboard or wood stud walls, will reflect sound back and forth through the acoustic material and increase the effect.

Should you really need that music studio and drum kit, specially designed high quality acoustic foam tiles can be applied to all surfaces to deaden the acoustics and prevent sound transfer.

One final thing to add for effective soundproofing is to have, at minimum, double glazed windows, which will also help with heat loss.

Give us a call on 0800 046 1995 if you need any help.