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- 17 Feb 2006
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I'm about to do a downstairs toilet ceiling. The roof above it is a flat roof.
Plan - not bother trying to stuff mineral wool in between the rafters because a)it's a pain, b)there's a nice ventilation space there without it.
Instead. fix Celotex/Kingspan/whatever PIR type board I can get up to the underside of the joist. Then underneath that make a frame for the plasterer to fix his plaster boards to. It's a really small room (1650x650). But to do it without any joints I'll have to buy a full 8x4 sheet of PIR.
Questions:
1. Does that sound like a sound structure? For moisture control I'll either pin some DPM up just above the plasterboards. Or ask him to use the board that's got moisture control built it.
2. If I have to buy a full sheet which is way more than I need. Is there any problem with buying have the thickness I want, and doubling it?
Cheers, Mike
Plan - not bother trying to stuff mineral wool in between the rafters because a)it's a pain, b)there's a nice ventilation space there without it.
Instead. fix Celotex/Kingspan/whatever PIR type board I can get up to the underside of the joist. Then underneath that make a frame for the plasterer to fix his plaster boards to. It's a really small room (1650x650). But to do it without any joints I'll have to buy a full 8x4 sheet of PIR.
Questions:
1. Does that sound like a sound structure? For moisture control I'll either pin some DPM up just above the plasterboards. Or ask him to use the board that's got moisture control built it.
2. If I have to buy a full sheet which is way more than I need. Is there any problem with buying have the thickness I want, and doubling it?
Cheers, Mike