We always use our closed cell foam which has a silver foil and is pre glues and is easily cut to fit in-between the support beams in the roof, item number 185653630204. The wood is a handy size to be able to screw up to the roof and then covered we always add our 3mm cloced cell foam on top of the wood before the material so we get extra insulation and a nice professional finish, item number 175485794298.
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