REMOTE: Drainage cavity between insulation and exterior membrane?
The REMOTE Manual does not indicate that a drainage cavity is needed between the rigid insulation and the exterior membrane. Lstiburek’s “The Perfect Wall” article, which is a similar assembly (or the same?) does not suggest this either. Has anything surfaced in the last few years to suggest a cavity is needed between these layers?
I’m in zone 4A, planning to use foil-faced polyiso. I have not selected the membrane yet.
I’m also planning to seal the polyiso on the outside face, hoping to keep most water on the surface and let the membrane act only as back-up. Innie windows means I’ll need to direct water outwards, with more flashing to the membrane as back-up.
I will use treated 1×4 furring to create a rain screen cavity.
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