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What to do with inactive rafter vents ?

tundracycle | Posted in General Questions on

A rafter space has a foam durovent soffit to ridge vent covered w/ 7″ of closed cell spray foam. Near the soffit a hole is cut through the foam & durovent to install a 14″ exhaust duct for a range hood blower. Obviously a gob of warm moist indoor air is pouring in to the durovent and it needs to be closed off.

– Good enough to just seal it near its base? This leaves the question of moisture build up in the inactive durovent space causing the sheathing to rot.

– Or should the entire vent space be filled with foam to prevent as much moist air as possible from hanging out in there?

Other thoughts?


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  1. tundracycle | | #1

    One option that our builder proposed is to put in some 2.5" flex pipe to join the lower rafter vent/soffit vent with the upper rafter vent/ridge vent and so allow for some air flow through the vent to prevent moisture buildup. ??

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