Attic Temperature Vs Room Temperature

It was 92 93 yesterday and sunny and my attic was 135 by late afternoon.

Attic temperature vs room temperature.

Calculations indicate that on a july day in texas a ventilation rate of one air change per minute for a typical attic using 95 degree f air will lower the peak attic temperature to about 101 degrees f. Summer attic air temperatures with reflective roof peak at or slightly above outdoor air ambient. 63 9 f as was the case for the ceiling cavity and eave space temperatures total r value does not tell the whole story. Attic temperature 0 f outdoors calculated difference.

Ideal attic temperatures shouldn t be more than 10 to 20 degrees hotter than outside temperatures. Heyer 1963 reported temperature histories for wall and roof. Providing half air change per. Attic temperature depends on the amount of solar radiation construction details and the rate of ventilation.

Now if the ridge vent is only partial or if the attic air temperature is excessive 20 degrees higher than the outside air fans may prove beneficial pick the right fan. Each change had the potential for affecting the in service temperatures to which wood roof systems were exposed. Built in passive attic ventilation or active mechanical attic ventilation. Basements attics and crawl spaces attic temp vs outside temp what is acceptable for attic temp vs outside temp.

Summer attic air temperatures with old terra cotta colored asphalt shingles peaked at 140 to 145 at 18 above the blown in fiberglass insulation layer at the attic floor. The layer of continuous insulation in the 2 4 wall shields the highly conductive steel stud from exposure to near outdoor temperature. In addition structures were better insulated in an attempt to make them more thermally efficient. In other words with proper ventilation gravity an attic in the summer with an outside temp of say 95 the attic should be.

The consensus seems to be that if you have the maximum amount of insulation in your attic floor for your area lowering the temperature of the attic by 10 or even 20 degrees will have a minimal if any impact of actual heating and cooling costs.