Sound proofing for ceilings!

[LittenTree]

We are going to convert our internal garage to a sitting room. DS1's bedroom is directly above it (which is probably why it's a touch colder than the other upstairs rooms).

We will do the obvious about insulating the floor, the walls are already double skinned (12 year old house) but what reasonably economical product can we use to line the ceiling to stop TV noise transmission from this new sitting room to DS1's bedroom?

the floor is probably packed with lightweight mineral wool same as is used for loft insulation. It is mostly made of air with a tiny amount of fibre.

To block sound you need heavy mineral wool batts. Obtainable from builders merchants and Wickes. they are much heavier, come in slabs nor rolls, and the extra density blotts out airboune sound much better. It will not blot out impact noise so well, you need a heavy felt underlay and carpet.

If the ceiling would benefit from replastering, an extra layer of plasterboard and a skim will make a noticable difference. If there are any holes in or around the ceiling, for example for pipes or if someone has poked lights through holes, block them up solidly.

Thanks!