Venting rafter bays at covered patio?
greenerCO
| Posted in General Questions on
I have a project under construction with a covered patio that has a vaulted ceiling that will have doug fir t&g (with clear-coat finish) covering the roof rafters. The contractor installed a ridge vent and wants to vent each rafter bay at the eaves to vent/protect the backside of the t&g ceiling. Is this necessary given that it’s over an unconditioned space? It seems venting of the cavity would occur naturally through the t&g/joints. Though, perhaps the clear coat finish creates enough of a barrier to allow some humidity to get trapped in the bays? Project is in the Denver area (climate zone 5, low humidity).
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Replies
greenerCO,
This is what Bill Rose said:
"I would expect the overall performance of a vented porch roof and a porch roof without vents to be about the same."
This is my take on it:
https://www.greenbuildingadvisor.com/question/vent-or-no-vent-for-covered-porch
Now one argument for venting (and insulating) is that covered patios often evolve into three season or fully conditioned rooms over time. If that's possibility it might make sense to do that work now.
Thank you!