Insulating the Attic and Cool Roof Technology

The sun tends to heat conventional roof shingles up to temperatures as high as 140 or 150 degrees F during the summer. That heat is then radiated to the attic, which reaches scorching temperatures, usually 40 to 50 degrees hotter than the outside air. The heat in the attic then radiates through the ceiling into the living areas making your whole house uncomfortable. To make matters worse, some homes have air conditioner ducts running through the attic. Picture this: you pay for the electricity to run your air conditioner to cool the air down to 50 degrees, and then run the cold air through metallic ducts in the attic, that are baking at 150 degrees. Your air conditioner will have to work much harder to keep up, and your cooling bills will be extremely high, especially if you live in warmer areas of the U.S.

Read Full Video Transcript Below:

Hey, this is Larry Janesky from Dr. Energy Saver. I want to talk to you about cool roof technology. The sun heats up a roof to an amazing 140, 150 degrees, or even more in the middle of the summer and in southern climates; this is most of the year. That heat, then heats up the plywood sheathing underneath and that heat radiates down into the ceilings of the house. The heat radiates through the drywall ceilings into the living space and makes your house more uncomfortable. You have to run the air conditioning a lot to get rid of this heat, aside from the fact that the ducts that run through your attic are baking. Then we are trying to run cool air from the air conditioning system through them to rooms we want to cool. It just doesn't make any sense. So, our attic could actually heat up to 130, 140 degress even when it is really 90 degress outside. 40 or 50 degrees hotter than the outside air temperature in the summer because of the radiant heat from the asphalt shingles, from the thermal mass of this asphalt radiating down through the roof. What do we do about it? Well there are radiant barriers on the underside of the roof. We can insulate the roof, insulate the attic, to prevent that heat from going down through our ceilings, but there is another thing we can do. When we re-roof, we can use roof shingles that have cool roof technology. The granules in the shingles themselves are especially engineered so that they will reflect heat and you know a white roof will reflect the most heat, a black roof will absorb the most heat and be the worst. But nobody wants a white roof; people like to have their browns and their charcoal grays. And so even with those colors with the cool roof technology these granules have a ceramic coating baked on them similar to firing a coating on ceramics and it can reflect up to 40% of the heat that it would normally get for that color back into the atmosphere, rather than absorbing it and radiating it down into the attic. So, if you are going to have your roof replaced, anyway, look for cool roof technology and buy the right shingles.