Unsafe Attic Temperatures

What should the attic temperature be relative to the outside and house temperatures assuming a new supposedly well insulated house.

Unsafe attic temperatures.

Most attics aren t made to walk in and insulation duct work and low clearances just increase the difficulty. See webb site address above for full text. Install electric ventilators and attic fans which remove hot air from an attic. Ideal attic temperatures shouldn t be more than 10 to 20 degrees hotter than outside temperatures.

If this isn t bad enough add to it the fact that an attic can reach temperatures of 120 degrees on a hot summer day. The white roof lowered the attic temperature by about 20 f. In some cases attic temperatures can reach above the 150 degree mark. Excessive heat deteriorates items you store in the attic and can cause moisture problems in your house.

If your attic is not properly ventilated your cooling costs will not be as low as they should be because your system is constantly running to compensate for the excess heat. They have done much of their testing in las vegas and phoenix where conditions are the worst and 150 degree attic temperatures are common. January 8 2010 5 15pm text size. It s also been found that roofing design and materials have more effect on attic temperature than ventilation.

They have thermostats that turn the fan. To head off these problems consider these options for bringing your attic s temperature down. High temperatures inside your attic shorten the life span of shingles. Field monitoring of numerous attics has confirmed that the temperature of the roof sheathing of a unvented roof will rise by a few to no more than 10 f more than a well ventilated attic.

I have to go into attics all the time and believe me i don t look forward to it.