Insulation board without membrane
Posted: Thu Jan 19, 2023 5:52 pm
I have a 1930s semi with original roof. The roof is dry, but it's just tiles - no membrane.
Is it ok to install 50mm insulation board between the rafters (leaving a 50mm gap between board and tiles) without a membrane?
Is it ok to install 50mm insulation board between the rafters (leaving a 50mm gap between board and tiles) without a membrane?