Wall insulation ??

[nottsrob184]

I am converting the back of my garage into a downstairs loo which can be accessed from the house...(when i knock the wall through.).
I have building regs inspector round and he says i need celotex timber frame insulation between my new loo and the garage....timber frame is 100mm thick.
This is well expensive, is there anything i can use that is cheaper that will satisfy building control officer?
Thanks for any advice.

 

[DevilDamo]

Are you asking for an alternative to Celotex or timber frame?

Timber frame is by the far the easiest and most efficient way of achieving the u-values as requested by the BCO. Celotex is not the cheapest form of insulation and there are other alternatives, which can provide the same thermal resistance. However, Celotex is preferred and most commonly used due to its workability as the boards come in sheets and can be cut down to size to suit stud spacings, etc...