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Insulation in roof

Hi I have just had my roof replaced on my garage, joists ply wood, felted etc, I now wish to clad the ceiling, I have celetex 3 inches thick to put between the joists and I want to clad it. There are no soffits and no air flow, will the felt roof sweat and expand if I put celetex on and then clad, or should I just clad it and what clad should use plastic or wood please help.

1 Answer from a MyBuilder Roofer

Dear Customer

Cellotex or other brand insulations should be used on warm habitable roofs to retain heat and reduce carbon footprint and saving energy prices . Your roof is a cold roof hence why the tradesman put the insulation between the joists you should have this ventilation with 50mm gaps between the insulation and the bottom deck of the flat roof to allow air flow outside in regulation with code of practice Bs 5250 2011 of building control .

You should also have ventilation vents in your soffitts to let your roof breathe this is advisable also - upvc cladding and soffitts are cost effective maintainable and come with a guarantee between 10 and 15 years also . Hope this helps happy to answer any other questions you may have .

Roof Professionals Direct


Answered 23rd May 2017

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