CONDENSATION? ROGER RECOMMENDS:
Cromar Vent 3 high-performance breathable roof underlay
▶ https://www.cromarbuildingproducts.com/products/vent3
DuPont Tyvek Supro Breather Membrane
▶ https://bit.ly/3cjJoyH
Klober Permo Air Vapour Permeable Air Breathable Roof Underlay
▶ https://klober.co.uk/product/pitched-roofing/membranes/permo-air
Thermafleece Breather Membrane 100gsm
▶ https://bit.ly/3nosZ2s