On 01/01/2021 19:35, wrote:
I'm now looking at these easy-fit devices to modestly increase natural ventilation on the back of the roofing felt, has anyone used these?
https://www.amazon.co.uk/dp/B00M97O5...v_ov_lig_dp_it
Thanks
S

You can achieve the same with chunks of expanded polystyrene
pushed into the overlap midway betwen joists. Much cheaper,
but doesn't solve the underlying problem of reducing the
amount of moisture vapour getting into the loft.

Fire hoods on downlighters are a start, but even they are not
a vapour barrier so you might want to make up your own downlighter
covers out of something fermacell or other class O board material
and cover them with turkey foil too.