Attic Temperature Too Hot

If it s 90 degrees outside the attic temperatures shouldn t.

Attic temperature too hot.

Unless your roofing system has insulation on the roofing deck and is designed without ventilation your furnace should not be heating your attic. Hang pencil and paper next to the thermometer and record the outdoor and attic temperatures for several hot days. Ideal attic temperatures shouldn t be more than 10 to 20 degrees hotter than outside temperatures. Whether it s 110 f or 130 f there s not much difference in the amount of heat flowing from the attic to the living space below.

An unventilated attic can reach 150 degrees in the heat of summer 50 degrees higher than it should be. But by adding powered attic fans you will draw more air into the attic. If hot air is allowed to sit in your attic it could overheat the shingles on your roof and cause damage. An overheated attic can bake asphalt shingles on the roof and cause them to deteriorate.

That is certainly too hot but how hot is ok. Having a properly vented attic is the best way to keep attic cool because it allows the hot air to escape during the summer. Thanks to the radiant heat affect attic temperatures on a 100 degree day can reach 170 degrees or more. The thermostat will usually start at 95 degrees fahrenheit which is the temperature that the attic fan usually starts at.

Note excessive heat. Just make sure the ceiling is airtight and fully insulated and the temperature in the attic doesn t matter much. Using insulation only keeps the attic s heat from traveling through your home. Poor insulation is usually the culprit although if you enter the attic on sunny winter day your attic space can be warmed by the sun more than your furnace.

This is because the attic is essentially open to the outside air. At the very best conventionally ventilated attics can never be cooler than the outside air temperature.