Ventilation – Ridge Vent / Soffit / Gable
Zone 4 in NC (Raleigh)
Attic/3rd floor recently finished and the area has open cell spray foam from soffit vent to ridge vent. Prior to spraying the livable space, the foamed space had a gable vent (now sealed), ridge vents at all top points, and soffits throughout. There’s another gable vent that is not sealed on the opposite end of the livable space/house with a much lower roof that I keep the access door closed (reachable thru mechanical room, that is foamed as well). I don’t consider it part of the 3rd floor since it has a lower roofline / not livable (much duck down to walk).
Question – I’m getting a roof replacement soon and don’t want to rely on roofers since they don’t specialize in building science. Should the gable vent be sealed off so there’s a ridge vent (not spray foamed) and soffits (not spray foamed)? I’ve seen many articles that say a ridge vent + soffit is all you need and to seal the gable vent (after adding a ridge vent by roofers) – but this house built in 2007 had all 3. Best to seal the gable vent? Prior to finishing the 3rd floor, there was free flowing air opposite the remaining gable vent but now that wall is sealed with open spray foam. Does this change anything?
Links to support one way or another?