Radiation coming from our sun is less during the winter months. As the earth tilts away from the sun we go from summer to winter and get shorter days. The atmosphere actually acts as a barrier reducing the amount of radiation reaching your roof. Your attic shouldn’t get much warmer than the outside in the winter because of its heat gain is coming from your home. If it is properly sealed up you might get a 10 degree gain, but that would be rare.
Originally posted by newhomeboston
Maybe I'm just thick, but why won't the solar gain warm up the attic air hotter on the inside causing the snow to melt even if its just below 30 outside where the melt will freeze down?
Also, isn't my ac going to work a lot harder than it should in the summer as I can envision 150 degree days once it hits 100 around here if it gets to 130 on sunny 80 degree days. That's OK???