Noise - Environmental - Insulating the Home - Floors & Ceilings
here and then search for "noise" to find the proposed revisions to the Building Regulations which cover conversions
and suitable sound insulation treatments to floors.
Sound transmitted through floors falls into two categories; airborne (speech, music etc.) and impact (footsteps). Impact sound can be greatly reduced by a soft floor covering such as carpet on thick underlay, but this would not affect airborne sound. An effective way to improve both types of sound insulation is to construct a new ceiling supported on independent joists below the existing ceiling.
Naturally such treatment is only possible where the rooms are high enough to permit a loss of 150 mm or more. Alternatively, the sound insulation may be improved to some extent by filling the space between the floor joists with a heavy, loose fill "pugging" material. Examples would be dry sand or high density pelleted mineral wool. You must ensure that the structure can support the extra weight!!
A further alternative would be a 'floating' floor, for example the top "floating" layer would consist of 18mm Tongue and Groove chipboard, bonded to a layer of 19mm plasterboard; The top layer would be laid on a spongy layer which should be 25mm mineral fibre having a density of around 100kg/m3 or similar; this spongy layer would extend up around the floating layer to provide isolation from the walls, the gap between the floating layer and the walls being around 10mm. The spongy layer itself would lie upon or could be glued to the existing floor after any gaps or cracks in the floor had been made good. It is important that there are no fixings through the top layer into the existing floor, as this would damage the structural isolation. The increase in floor height would be around 60 mm, which can cause considerable problems with doors, skirting boards, power sockets and so on.