During renovating the back of house and extension ive found the extension to have just 100mm rockwool insulation in the flat roof. I just want to explore options when putting new insulation back in to maximise the effectiveness of the insulation.
Joist size = 200mm
Room size 5.6m x 5.7m
Roof size 5.6m x 1.6m
I was toying with the idea of 75mm Celotex / Kingspan with 100mm rockwool. There are a couple of pipes up there and there will be firerated led spotights being installed also.
Thanks in advance for any suggestions.