Integral Garage roof insulation.

[Owdcodger]

Hi. This is my first venture I apologize in advance if I break protocol. My son in law has a house with an integral garage and bedroom above which is much colder than the rest of house. The garage ceiling has an asbestos type fire resistant sheeting and he is proposing to put kingspan over this rather than remove panels and insert it between the joists. Is this practical and will it be any improvement.
Thanks
Owdcodger

 

[noseall]

Practical - mebbe.

Improvement - definitely.

Make sure all joints are sealed either with foam, foil tape or mastic.

He will need to use 100mm thickness or so.