I've currently got the floor up in the bedroom to move a radiator and wondered whilst it was up whether it was worth putting standard loft insulation between the joists to help with soundproofing the room from below? Is there any problem with this with regards to Health and Safety??
No there is not a problem providing you do not encase the wiring under the floor in the insulation. It is better to use a dense mineral insulation like rockwool which has better sound-proofing capabilities.
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