Soffit vents for main roof under porch roof
LostHomeowner
| Posted in General Questions on
Help! Remodeling a home. The inside is gutted to the studs. We are adding a porch roof which overlaps the main roof several feet up. My contractor was not putting in soffit vents. I insisted so he wants me to tell him how and where to install them. The main roof ends over the windows and slider to the porch. The porch roof connects to the main roof several feet above. Do we build a box over the windows and doors or can we vent the roof through the porch soffits? If we did the latter, air would enter the house rafters several feet above the main roof soffits. Or can we install vents on a vertical surface?
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Replies
LostHomeowner,
Either works fine. As long as they are continuous from intake to outlets they will both work. Any moist air in the bottom several feet of roof will move upwards and into the vent channel if you go that latter route.
Is this an open porch or a closed and conditioned porch? If it is closed and conditioned with a sloped ceiling, then soffits vents in the porch eaves would be appropriate, and you have to make sure that the ventilation space is open where the porch roof meets the house main roof so that you have continuous ventilation from porch eaves to main ridge. If your contractor laid a ledger on top of the main roof rafters to act as a seat for the porch rafters, this might be difficult. A sketch or photo of what's built already would be helpful.
If this is an open and unconditioned porch, then soffit vents in the main roof eaves (inside the porch) would work fine and the porch roof doesn't need any ventilation besides making any ceiling finish somewhat porous.
It’s an open porch. See photos. And thank you for your help.
Also see drawing attached ( close but not exact).