Wall insulation thickness.

[crossy67]

I am intending to dry line the rooms we are renovating with Cellotex as an insulation between the plaster board and stone wall.  What thickness would people be going for?  I want it as thin as I need I want to make the house warmer but don't want to loose too much space, that and the thicker the insulation the more it's going to cost.  I was thinking somewhere between 25-50mm, would 25mm be enough?

[fisherman]

We recently completed a UK extension. I built it from Celon thermal blocks 250 thick. In order to comply with the UK regs we needed 70mm foam backing on the plasterboard. We find that in the very cold weather this seems to be reasonably efficient.

If you have a solid stone wall you will probably need about 100 thick to be effective. Just a guess mind. Find the manufactures web site & they should have information on u values & possibly a ready reconer.

Like you I did not want to loose too much room space but to be honest when done you will not notice.

[La Guerriere]

You can get foam backed plasterboard with up to 100mm foam, which you clag on with adhesive. If you want to use Cellotex, maybe think 70mm as you can get the metal framing (rail et montant) in 70mm. The usual is 50mm but it's a bit thin even for good insulation.

[Théière]

[quote user="fisherman"]

Like you I did not want to loose too much room space but to be honest when done you will not notice.[/quote]

And that's the truth!