Airtight and ultra-insulated home feels cold all the time
My wife and I just built a 1.5-story home that is 2700 square feet down 800 up. The downstairs has a 4 ton Trane XR15 air conditioner and the upstairs has a 2 Ton XR15 air conditioner. Heat is run on propane since we don’t have natural gas in our area.
Our walls are 6″ thick and filled with cellulose. Before insulation was applied I sealed EVERY seam, crack, nook, or cranny with spray foam or caulk. I did not bother with the expense of a blower test, but it should be very tight. The attic is vented and the ceiling has about 21″ of Insulation on it. Way more than is ever used in Houston, Texas. Low-E SC windows throughout.
Anyway, for all this, it always feels freezing cold to us. At 70 degrees in the winter we have to wear a coat. We are not really comfortable until we hit about 72-73 degrees, which seems pretty high to me. In our old house, we use to keep it at 70. The odd thing is that in summer we have too cool it colder as well to be comfortable. About 75 degrees, whereas our old house we kept at 78. Of course it ran non-stop to get down to 78.
Could this very small disparity in our perceived comfortable temperature be do somehow to the tightness of the home? Convection from outside sources are all but negated. Radiation through the windows should be minimized. The only effects we should be getting is radiative heat to the walls. I measured them to be about 67 degrees when it was 30 degrees outside.
Part of me wonders if it is because the heater/AC runs so much less and therefore the air does not feel as comfortable. I knew a two stage unit would have been better, but we had to cut corners somewhere to afford this thing.
Another thing to note is that the upstairs feels warmer even at a lower temperature. We can be up there at 69-70 degrees with no problem at all in the winter. We almost NEVER run that unit since the heat from downstairs rises up there.
any thoughts are appreciated.
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