Please at least read this first post.
It doesn't appear that this specific situation (especially no possiblity for soffit vents) has been addressed before.
My wife and I moved into a two-story 1969 frame home in Chicago suburbs that has:
- NO Soffit vents and house style PROHIBITS creating them. (The roof line cuts into the second floor and creates a "cove" on second floor rooms.)
- Approx 1300 sq feet attic space.
- The original whole house fan (which nicely cools off the second floor in 15-20 min on the hottest week day evenings after coming home from work when opening basement windows -- concrete basement floor dehumidifies the air). To try to minimize winter heat loss, I made a plywood box with removable lid that is insulated by the blow-in insulation on the sides and fiberglass matt on the top.
- about 9" of original fiberglass batt in attic PLUS 18" of new blow-in insulation.
- Large N-S gable vents totaling approximately 6+ square feet.
- new asphalt roof, but it has a cheapo ridge vent consisting of what looks like a big brillo pad.
- New Lennox furnance and A/C.
- three wood fireplaces (one with a new wood insert). The other two will be sealed soon.
MY IDEA I'm seeking feedback on:
- Installing a power attic vent to cool off attic with the hopes of permanently closing up the Whole House Fan.
Given the existing 6+ square feet gable vents and in ability to install soffit vents, this appears to be one of those rare times when a Powered Attic Vent may help to minimize A/C usage.
P.S. All the duct work in the house (90% plus behind walls/floors) appears to be leaky.
P.S.S. This is our first house. Had I known what I know now about HVAC, building envelope, etc, we wouldn't have bought the house.