Soundproofing a Garage, or other outbuilding .

We are often approached by drummers and bands who wish to create a practice environment at home in a garage or shed. The following article gives some guide on how to achieve this environment at the least possible cost. However, the material costs alone can be quite substantial. As a guide, the cost of the materials for the room within a room structure, of dimensions 4m by 2.5m by 2.4m would be between £950 and £1080 depending on final specifications. This provides just for the internal walls and ceiling, plasterboards, mineral wool, resilient bars and mastic.

Still interested? Then read on.

One of the important things to realise, when attempting to soundproof a garage or similar outbuilding for use as a music studio, is that in practice it is very difficult to achieve a completely soundproofed structure.

Where the garage is attached to your house or your neighbour’s house the structure-borne sound (i.e. the sound that gets into attached structures) can be more of a difficult issue to deal with than airborne sound. Remember if you are in an area of reasonably high ambient sound (i.e. near a road or busy street) the soundproofing will appear better than in a very quiet neighborhood.

When attempting soundproofing of a structure you are faced with two choices, a room- within-a-room which uses up a fair amount of space, or trying to clad the existing structure with soundproofing materials. You must remember that the windows and doors are the weakest link in the chain, and as such should be looked at first. This is because the sound will continue to leak through these points whatever you do to the walls and ceilings.

When dealing with windows and doors these should ideally be bricked up. If you have one of the sliding up-and-over metal doors this should either be removed, bricked up or a brick wall built directly behind it. The door itself can be upgraded using a rubber mat and acoustic membrane then sealed shut with mastic. However this is far from ideal and will represent a weak point.

THE ROOF and CEILING

Brick or block walls are much better than a tiled roof when it comes to stopping sound penetration. Typically when soundproofing a garage it is the roof which offers the weakest link in the existing structure. In addition to any work carried out to the ceiling you might wish to augment the roof structure with a double layer of plasterboard and mineral wool.

A second inner ceiling then would need to be added with at least a 100mm layer of mineral wool resilient bars and a double layer of plasterboard. http://www.soundstop.co.uk/solutions/ceiling_access/ceiling_solution_1.php

THE WALLS

The walls should ideally be stud work, that is independent (sits away) from the existing external wall structure. Again the walls should comprise a 100mm layer of acoustic mineral wool (at least 60kg/m3 density, preferably 100kg/m3), resilient bars and a double layer of acoustic plasterboards. http://www.soundstop.co.uk/solutions/wall_solutions/wall_solution_4.php

The internal acoustics of the room you have created need to be addressed by the addition of absorption materials so as to create a non-reverberant space.

Ventilation will of course be an issue so some form of air inlet/outlet will need to be mounted onto a wall.

Remember that this offers a guide on how to achieve a soundproofed garage but the actual performance relies on a series of factors:

• The amount of isolation you can get from the existing structure. (i.e. can you create a room within a room?
• How much bass are you producing? Bass sounds and low frequency sounds are much more difficult to soundproof against
• Is the existing structure brick work/heavy block or lightweight breeze block? The latter performs worse as a sound-proofer.
• What is the background noise in the area like, will sound leakage be lost into an already noisy environment?

Finally the above represents an ideal world environment if you can achieve any sort of room-within-a-room structure you will have gone some way to creating a soundproofed studio.

Read the following links that will give you a guide to costs for each of the structures.

The walls

http://www.soundstop.co.uk/solutions/wall_solutions/wall_solution_4.php

Ideally use 100mm independent stud walls.

The ceilings

http://www.soundstop.co.uk/solutions/ceiling_access/ceiling_solution_1.php

Ideally you should think of an independent ceilings here as well.