Reasonable to vent a warm climate garage?
I have a new house with a west facing garage in Raleigh, NC. There is a 40 foot shade tree with pretty good coverage. I insulated the garage to basically a code minimum for conditioned space with a R11 double door. It has one wall attached to house and nothing above it.
The house is 2×6 with Zip R3, mix of foam and blown fiberglass. HERS 50 (-7 with solar).
The garage has 2 Teslas (as well as batteries for mower/edger/blower).
This morning the garage was 83 with an outside temp of 68. No charging, no driving after 4:30. Yesterdays high was 85 or so.
I frequently find myself leaving the garage door open to cool it off but there are lots of critters around including ticks. That doesn’t go over well.
So I have considered a fan to the exterior – with an passive intake. Not for the 50 cents a year saving on a/c of the house but to protect the batteries. Probably irrational but the last car was a Leaf so I am a bit sensitive. Had some degradation but not warranty level. Sold after 6 years.
My experience with open windows at our last house was that you could easily get to within 10 degrees of outside temp but not much better. That was a much bigger volume of course and I was not using a fan.
In the spring and fall of course the exterior air temp will be 50 in the morning and the garage will be 75 but probably up to 85 in the early evening.
Most of the car charging is mid day when solar is fired up or early AM topoffs. Hard to say how much this contributes to heat load – certainly not the early AM charging.
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