As temperatures remain high in portions of the country, many homeowners will suffer from significant comfort issues and wasted energy in their homes as a result of conditions that have not been addressed in their attic. If you find yourself suffering from these issues this cooling season, it may be worthwhile to consider the following potential causes:
1. Leaky, under-insulated ducts in attics.
Many homes have air conditioning systems and ductwork in their attics. These systems are designed to produce and distribute the correct amount and temperature of air to cool your home and increase your comfort during the summer. Unfortunately, a large percentage of that air is lost along the way due to duct leakage. Up to 47% of the air you paid to cool can be lost through holes, gaps and poor connections in your ductwork.
Attics are a hostile environment in your home. In summer, the cool air produced by the air conditioner is re-heated by the metal, under-insulated ducts sitting in 130 degrees+ attics. Your ducts act as re-heating lines – warming the air as it travels from the air handler to your rooms. The cold air you spent money to cool never reaches the rooms you want to make cooler and more comfortable. Now the air conditioner must run longer to deliver the comfort you want, raising your electric bills. (In winter, the opposite occurs. Hot air produced by the air handler is re-chilled because these same ducts are in 30 degree and colder attics!)
2. Not enough insulation on attic floors.
During the summertime, the sun bakes the shingles on your roof, and this heat transfers through the shingles, heating the roof deck inside your attic. The roof deck then radiates heat into the attic heating up the air. This causes attics to be extremely hot in the summer, as high as 130 or even 140 degrees depending upon where you live.
Many attics do not have enough insulation on the attic floor to resist the movement of heat in the attic through the insulation and into your living area. This heat moves to your ceiling drywall, making the upstairs ceiling surfaces very warm, and turning them to indoor radiant heaters during the summer. This hot surface radiates heat to you and your family – therefore your upstairs may not cool down until well after the sun goes down and the attic has a chance to cool off. Your air conditioner must cool off all the surfaces in your living area as well. Hot ceilings cause you to have to run your air conditioner longer, wasting your money.
To help you stay cooler in the summer, it is recommended that your attic ducts are air sealed and well insulated. Measure the amount of insulation you have on your attic floor – if it doesn’t cover the floor joists – you need more.