Do I need to install both Housewrap and foamboard when residing a house
GBA Editor
| Posted in Energy Efficiency and Durability on
I am residing a house and the question has been brought up about installing blue board (foamboard) and a housewrap, but I don’t believe both are necessary. Can’t you do just one or the other?
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Replies
Neither are necessary.
But, if you want to improve the thermal performance of the house (by reducing thermal bridging through the framing), then installing some exterior foamboard may make sense.
If you want to control water infiltration through the siding and into the sheating, insulation and framing, then housewrap may make sense.
You can try to perform the latter function using only foamboard, but then you're relying on taped joints to permanently seal against water intrusion, while properly-installed housewrap is shingled (overlapped downwards) to allow drainage and prevent water infiltration.