Wood fibre in pitched roof

[ColdProof]

Hi

So when talking about wood products on the page on Analysis, interpretation and assessment of the calculation results (https://wufi.de/en/service/wufi-forum/? ... bd265076bd) does this include flexible wood fibre in the same category?

See attached results for the WME% in the outermost 1cm of flexible wood fibre in a pitched roof construction modelled according to WUFI guidelines, with external breather membrane (0.1 sd) and internal variable humidity membrane. It seems to get up to 45% which is way over the 18-20% guideline, but as it's happening when temperatures are low, then are we to assume in this case it's fine? So then looking at RH, it's a max of 95% RH at the top of the wood fibre under the breather membrane during the cold periods, so taking the WTA approach (where it must not exceed 95% at 0°C and 86% at 30°) then I guess we're OK?

[Christian Bludau]

Hi,
until now, the WTA curve has actually been intended for softwood. However, many wood fiber insulation materials are even more durable than wood, but not all of them. If in doubt, this should be clarified with the manufacturer—for some materials, this is already known, otherwise testing options will soon be available.
Christian

[ColdProof]

OK thanks for the info