Attic and Ambient Temperatures
Norman Bunn| Posted inGeneral Questionson
Greenville, SC CZ 3A
I have a new Ambient Weather Station at my house and have placed remote temperature and humidity sensors in two disconnected areas of my attic. I have been surprised that the difference in temps in the attic and the outside temps is only 6-8 degrees F. So, when it is 90 outside, it is 96-98 in the attic areas.
This is a Pretty Good House with dark shingles over plywood with a radiant barrier on the attic side. It has a well ventilated soffit that is 2′ wide and a hip roof with ridge venting.
Is this range normal? I was expecting the temps to be in the low 100s.
Thanks!
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Replies
The closer your attic temps are to ambient, the better your venting is working. My attic tends to run around 120-130F on a 90 degree day, so I have some work to do :-)
Note that I’m assuming the attic isn’t cool due to air leakage from inside the house that I’m assuming to be air conditioned. You can test this by shutting off your air conditioning for several hours. If the temperature in the attic rapidly rises when after you shut off your air conditioning, then you have air leakage problems. If the temperature in the attic stays about the same, or rises only slightly, then you have good attic ventilation and things are working properly.
Bill