I have a bay window in my 1930 semi.
Before I close the roof in with plasterboard wanted advice on insulation. The roof is a simple slanting wood roof with what I assume is felt on the outside and lead flashing, no breathable membrane.
I was going to insulate by adding 50mm PIR insulation flush with the inner roof leaving at least a 50mm gap above where the wood boards are for air flow.
There are no vents but back part sits on steel beam where the flashing would meet the brick and can't see it being air tight.
Is this the best way or should I may it all warm right up to the wood slats, to avoid a cold roof?
The front of the bay is just tiles on wood with a breathable membrane on. I was going to leave this with no insulation and insulate the inner wall as then air coming through the tiles can circulate and dry any moisture.
Any advice would be welcome as not sure which way to go.
Before I close the roof in with plasterboard wanted advice on insulation. The roof is a simple slanting wood roof with what I assume is felt on the outside and lead flashing, no breathable membrane.
I was going to insulate by adding 50mm PIR insulation flush with the inner roof leaving at least a 50mm gap above where the wood boards are for air flow.
There are no vents but back part sits on steel beam where the flashing would meet the brick and can't see it being air tight.
Is this the best way or should I may it all warm right up to the wood slats, to avoid a cold roof?
The front of the bay is just tiles on wood with a breathable membrane on. I was going to leave this with no insulation and insulate the inner wall as then air coming through the tiles can circulate and dry any moisture.
Any advice would be welcome as not sure which way to go.
