Hi there
I'm building a small extension. The plan is for a shallow-pitched warm roof (22 degrees). The architect chappy reckons that I should put 18mm birch ply as the 'deck' on top of the rafters (supported by a ridge beam) with 6" insulation and slates on top of that, leaving the rafters (supported by a ridge beam) left exposed inside the building. This is partly for aesthetics, and partly because there are headroom constraints, so having the roof structure open will help to give a sense of space.
I'm concerned, though, that this current plan will not give good sound insulation (PIR insulation basically has no sound proofing qualities at all and wood isn't great either). It is a worry as there is some road noise, and also one of the new rooms will be a utility space with a washing machine and I need to stop sound moving from room to room.
U value requirements means I am stuck with PIR insulation or similar, so any sound attenuation will come down to the panels used for the deck.
Cement boards, have been suggested as an alternative to ply, or wood wool boards. The engineer says they can be up to 15kg/m2. What do you think? Any other options?
Thank you
I'm building a small extension. The plan is for a shallow-pitched warm roof (22 degrees). The architect chappy reckons that I should put 18mm birch ply as the 'deck' on top of the rafters (supported by a ridge beam) with 6" insulation and slates on top of that, leaving the rafters (supported by a ridge beam) left exposed inside the building. This is partly for aesthetics, and partly because there are headroom constraints, so having the roof structure open will help to give a sense of space.
I'm concerned, though, that this current plan will not give good sound insulation (PIR insulation basically has no sound proofing qualities at all and wood isn't great either). It is a worry as there is some road noise, and also one of the new rooms will be a utility space with a washing machine and I need to stop sound moving from room to room.
U value requirements means I am stuck with PIR insulation or similar, so any sound attenuation will come down to the panels used for the deck.
Cement boards, have been suggested as an alternative to ply, or wood wool boards. The engineer says they can be up to 15kg/m2. What do you think? Any other options?
Thank you
