Garage Roof Insulation

[Gary]

Got a pitched garage roof similar to the house which is felted and tiled.

I plan to board the underside of the ceiling joists with plaster board. Can I use Celotex between the ceiling joists instead of rockwool?

Are there any issues in using ridged insulation between ceiling joists with a loft above?

Thanks

 

[MMUK]

Celotex is fine, it's standard on new build these days.