@McVities said:
I also wanted to find out – clearly 2mm of insulation is clearly insufficient underneath floorboards – what would normally be considered adequate? Is there any clear guidelines about this? (I will push for carpet and underlay, but I want to ensure that I have all the information.)
Our by-laws specify at least 11mm of quality insulation but I’m not really in favour of being that prescriptive since another imponderable is the thickness, density and sound transmission qualities of the actual slab.
If I were drafting a by-law, it would say that any changes to the flooring should not permit any increased transmission of noise (but I would then attach a guide to how that could be achieved in an average unit in that building).