You might think that there is nothing in common between an AC unit and your roofing material, but you would be wrong. The wrong roofing material can drive up your cooling costs by contributing to your home's heat gain. The right roofing can reflect the sun's rays and help to keep your home cooler. For the best AC efficiency, you should choose metal roofing instead of asphalt shingles.
The Problems with Asphalt Shingles
Asphalt shingles are made from—no surprises here—asphalt tar. This tar is dark in color and not at all reflective. Thus, the asphalt tar will absorb the sun's rays, and the more rays they absorb, the hotter the shingles will get. In fact, asphalt shingles can reach temperatures of up to 155˚ Fahrenheit. Some of this heat will stay on the outside of your house, but some of it will seep through to the inside. Though your attic insulation should trap most of the heat, some of it will leak into your house, and the hotter your home gets, the longer and harder your AC unit has to run, and the more you have to pay in utility costs.
The Advantages of Metal Roofing
Emissivity and reflectivity are both important in creating an energy efficient roofing material. Reflective materials will reflect the sun's rays away from your home before they have a chance to heat up your home. An emissive materials will release what heat it absorbs rather than retaining it. An emissive material will release some of this heat into your home, but some of it will go back into the atmosphere. Metal is naturally reflective, and so a metal roof should reflect a lot of heat away from your home, but metal is not very emissive, so it will retain heat which can then warm up your home. However, a metal roof that has been treated with an emissive coating will release what heat it does absorb. A good metal roof will help you to reduce your heating costs by up to 40%.
If your home continues to heat up even though your AC unit is running, the problem might not lie with your AC unit. instead, it could have more to do with your home's amount of heat gain. to reduce your home's heat gain, and give you AC unit a break, you should consider changing out your roofing material in order to reduce your cooling costs.
For more information about cooling and heating problems, talk to a professional like Century Heating & Air Conditioning Services.