Quote:
Originally Posted by the dufferz  If the attic ventilation is passive, then other than convective currents, it takes a breeze to make the ventilation work. I have been in attics that were at code (our code, 1 sq. ft. vent to 300 sq. ft. attic, 1/2 intake, 1/2 exhaust) and even in washington it sweltering hot. The only other option would be to use active ventilation. In our area that is mostly wired for humidity, not tempurature.
When I replace my roof, I went with a ridge vent, and that helped. |
Yes, the code is a minimum requirement. The minimum isn't adequate for low-pitched (3/12 prefab truss) roofs with dark shingles.
Experts recommend double the vent area required by code.
I mentioned it because it can really make a dramatic difference rather easily, and it is a relatively easy DIY project.
I had an overheated attic, so put in one 12" wind turbine. It did the job of keeping the attic not more than 20-25 F above OAT, and kept the entire house about 10 F cooler in summer. Then 20 years later, I reroofed with lighter colored shingles, and installed additional soffet vents and full length ridge vent instead. That also worked. So "code" isn't necessarily good enough (or let's say it might be in Seattle, but not in Pasco).