Keep Your Attic Cool

One of the easiest ways for your home to get really hot is to let air from the outside get into your home. Why would you let hot, summer air into your nice, cool, air conditioned home? Well it's not always on purpose...or things that you would automatically think of. Things to be aware of: * If you keep your garage door open - you are letting your home get hotter than it needs to be. Most garages, especially those built a while ago are not properly "sealed." Depending on the age, some of them might not even be insulated. This is a problem, because of course it's going to be very hot in the garage and once you let that heat in, it's adding to the heat inside your home - making your house harder to cool off. * Your attic can be very hot. That hot air can make your home considerably warmer. How can we solve this? One way is to make sure that there is air moving through the attic. (If air is stagnant it in effect bakes and becomes hotter, if air is moving it doesn't get AS hot - it's still important to have insulation though.) Source: http://www.askthebuilder.com/B236_Ventilation_-_Keeping_Home_Attic_Cool_Naturally.shtml

"If you air condition your home, the last thing you want is air conditioned air finding its way into your attic and out the vents! This is why powered attic ventilation can be harmful to your pocketbook."

Your unit has to work much harder to cool a home that has been baking in the sun all day. It is much easier to keep your home cool if it stays that way. The longer your unit is on, the more money it is going to cost on your energy bills. If you can keep the air on for shorter periods of time, you will save money. Better yet, if you can use the programmable thermostat, you can save up to $180 a year.

Attic Heat

When it's this hot outside - the first place heat is getting trapped is your attic. Once it's in the attic, it's very easy to get into your home. So even if you're running your AC, it still may not be as cool as you would like it to be.

Hot air gets trapped in your attic, especially if there isn't a mechanism to move the air around (like an attic fan). The trapped air keeps getting warmer and warmer, and then scientifically heat transfers from warmer to cooler. So if the house is being cooled, the hot air from the attic is going to move to livable space. This is a very common problem, and there are some quick and easy fixes. Upgrades to consider:

1. Buy a reflective coating for your roof. (usually this is marketed for mobile homes, but it does help any roof). Make sure that you follow the instructions on the can and only use where directed by the instructions.
2. Another option is installing a radient barrier inside your attic. This is especially important for homes with a higher pitched roof. Sold at hardware or other improvement stores the barrier is a type of silver 'blanket' (for lack of a better word) that gets stapled to the inside of the roof (on the attic side) to prevent heat from entering. It's similar to those reflective cardboard thingies used in car windows to prevent the stearing wheel from getting too hot. Same Idea. Keep the heat out, and you'll have to cool it less.
3. More on the expensive side is adding a fan. There are several different types. The main two are an attic fan and a whole house fan. An attic fan is a small fan that moves air from the attic and increases circulation. This prevents the "baking" of air and cools the space which then helps the home stay cool. The whole house fan (is exactly how it sounds) which circulates air throughout the whole house, but can be loud and distracting.

If these upgrades seem like too much, you may want to consider adding more insulation to walls and especially in the attic. The less air that leaks, the cooler the air processed by your air conditioner can get. Things to think about...

Please DO NOT TRY this at home...

I am NOT advocating that you climb up into your attic - REALLY, DON'T. I just thought that it might be interesting for you to see what is similar to what's in your attic. It's just a precautionary tale about keeping up with maintenance of your units. once again, PLEASE DO NOT TRY THIS AT HOME. Just think of it as PBS- interesting, but not for you to go out and do with out a license. :)

Why Doesn't The House Get Cool?

This is a VERY familiar complaint during the summer! Your air conditioning unit will work when you turn it on, but sometimes we (as homeowners) make the unit work harder than it needs to! This article was borrowed from the Austin Texas Green Building Blog (as noted on the bottom enclosure) found at: http://www.greenbuilder.com/general/articles/AAS.atticcool.html

"This article first appeared in the Austin American Statesman. Don't Let Your Roof Take the Heat "Tips to keep your attic cool"By Marc Richmond-Powers, City of Austin Green Building Program

Picture this: It's a hot and humid Austin summer day. You head for the indoors and some relief from your trusty air conditioning (A/C) system. Three hours later, you're slightly cooler, but you're wondering why your A/C unit hasn't shut off yet.

Here's why: all day long, solar radiation has been heating up your home through the windows, walls, doors and especially the roof. Your attic temperature can easily reach over 140 degrees. That heat up there is working its way through your meager attic insulation into your home and through the A/C ductwork, located in your attic, into your cooling system. Your A/C system has to fight that added heat to change all that hot air in your home into cool air.You can install solar screens for the windows, porches around the house for shade, and plant trees around the home, but what do you do about the roof which accounts for a third of all the heat build-up of your house?

Here are a few options: Ventilate your attic with ridge and soffit vents. Vents are louvers, grills, or screen materials which allow passage or air through them. They are typically installed along the top peak (ridge) of your roof, at the top of the side wall (gable), and on the underside of your roof overhang (soffit). Ventilation moves air through your attic by force of wind or by heat rising through natural convection. This leaves cooler air sitting on top of the insulation on the attic floor. Ventilation also has the ability to remove humidity which has built up in your attic and which reduces the effectiveness of your insulation. It is often best to hire a contractor to install these.

Insulate your attic floor to R-30. R-30 is roughly a10 inch thick layer of insulation material above your ceiling. This is a job for any handy homeowner or it could be handed over to a contractor. When installing the insulation, be careful not to block your vents.

Install a radiant barrier between your roof and your attic insulation. A radiant barrier is an aluminum foil material which prevents 95 percent of the heat that radiates from your roof from reaching the insulation on your attic floor. It comes in a roll and is stapled to the underside of your roof rafters. Radiant barriers are sold in most building material supply centers and can be easily installed by a homeowner. This system can save you up to eight percent on your summer cooling bills.

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copyleft 1997: You are encouraged to copy and redistribute this article provided that you acknowledge the City of Austin's Green Builder Program as the source. Please attach this statement. "

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What are some other things you can do to ensure that your air is working at it's best? 1. Turn your air on early - BEFORE the heat of the day, IF you are going to be home. If you are not going to be home a thermostat that you can set is an especially good way to keep your home cool. Setting this thermostat to turn on at a very low rate while the home is unoccupied keeps the hot air from settling in the house, but still does not use too much energy. 2. Make sure to keep drapes drawn. If your home has skylights or larger windows, you might want to consider placing an outside screen or other heat reflecting material over these. 3. Set the thermostat to a comfortable setting (78 degrees if possible - this is the energy star recommended setting and will save you). If you set the degrees for as low as it will go in hopes that your house will cool faster, your unit is just going to burn out faster.