Roof ventilation – is it advisable to exceed code minimum

DBars | Posted in GBA Pro Help on November 5, 2024 03:28pm

If I well exceed the 1/300 nfva minimum set out in R806.2, can there be any issues with this?

I have 40% at the ridge and 60% at the eaves (split between two eaves of a gable), but my ratio is approx 1/75, roughly 4 times more nfva.

Thanks,

Daniel

Answer

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Malcolm_Taylor | Nov 05, 2024 03:36pm | #1
Daniel,

I can't see any downside to more ventilation. Maybe in hot, humid climates?
Expert Member

BILL WICHERS | Nov 06, 2024 08:49am | #2
There is some advantage to having more intake (soffit) than exhaust (ridge) ventilation, since more intake means less issues with a depressurized attic and it's resulting increase in stack effect within the home. The only place I can see venting to pose problems is in areas subject to high fire risk.

Bill