SOUNDPROOFING FLOORS AND CEILINGS
Noise transmitted by ceilings and floors could be either airborne or impact noise. Soundabsorbent tiles will not prevent either coming through the ceiling. As they merely absorb noise created in the room itself.
Soft furnishings and thick carpets do a lot to reduce the noise problem.
Sound passes easily through suspended floors: especially impact noise, which may even be amplified by them. One cure is to lay a 50mm layer of dry sand over the ceiling between the floor joists.
But make sure first that the ceiling is strong enough to carry the extra weight. If you are in any doubt, have a professional survey done.
Laying a sand barrier means lifting the floorboards. While you’re doing this. Lay a mat of glass fibre or mineral wool over the joists. Allowing it to hang down slightly between them. Do not nail the floorboards back down again: instead cramp them together and fix them to battens ‘which will lie between the joists.
When you relay the floorboards make sure some of the glass wool overlaps slightly all round. Tuck the wool into the gaps between floorboards and skirting board so the entire room is sealed off from below.
Solid floors also allow noise to pass through them. A thick carpet with two or three layers of felt underlay helps a great deal but this may not be enough.
As impact noise is the major problem with solid floors, you may need to construct a floating timber floor.
Lay expanded polystyrene or insulating wool over the floor and then build up a timber raft using 75mm X 10mm timber battens as a base with tongued and grooved panels or chipboard laid on top.
Leave an air gap all round the edges of the room and do not fix the battens to the floor.
Alternatively you can fit proprietary sound dampers between the battens and the floor. These are very effective in preventing impact noise from travelling upwards or downwards between floors.