Insulating Timber dormer

[Smath22]

Hello,

I need some advice on insulating the bedroom walls on my house, they are all timber frame, and basically consist of plasterboard, studs, then some sort of memebrane and tiles. There is no insulation at all.

Please see the pictures to see what i mean.

Untitled

• Smath22
• 14 Feb 2013
• 1

Untitled

• Smath22
• 14 Feb 2013
• 1

Untitled

• Smath22
• 14 Feb 2013
• 1

Untitled

• Smath22
• 14 Feb 2013
• 1

The current depth of the studs is 70mm. My plan is to remove all the exisitng plasterboard, and battern out the studs, and then install 100mm celotex, a vapour barrier and then replasterbaord and skim.

Is this a good idea or is there a better way? Am i going to get condesnation problems in the wall ?

 

[catlad]

regs say leave a 50mm gap from the tiles. I would also use insulated plaster board over the studs celotex PL 4000 comes with vapour barrier.

 

[Smath22]

If i dont leave a gap will this cause an issue with regards condensation, that is my main concern, I have trouble understanding the various dew points etc.

 

[catlad]

I would put 40mm between the studs and insulated plaster board over the studs leaving a 30mm gap, but I would also install over fascia vents and a ventilated ridge plus lap vents, that will sort any condensation issues.