Sometimes your Air Conditioners Ain't Broke

With the long history of contractors sizing equipment improperly because nobody wants to do a load calculation sometimes you can solve a nuisance temperature control problem by changing your environment, here are some tips to help. Even if your system keeps up allright there is no reason not to green up your home by increasing efficiency.

Cut summer energy costs with a radiant barrier

With warmer weather just around the corner, there may be a way to help keep rocketing energy costs from driving air conditioning costs skyward.

Radiant barriers are one more way you can help keep your energy costs at their lowest possible level by reducing winter heat loss and summer heat gain.

As your roof heats up during the summer, heat radiates from the roof surface. Some of that radiant heat is transferred to the air inside your attic or the air space between your ceiling and the roof, heating the air in that chamber. If your air conditioning ducts are in the attic, reducing the attic air temperature will also cut down on the heat gain in your air conditioning ducts.

Insulation traps air, providing a barrier that goes a long way in keeping that hot attic air from radiating into the living spaces of your home. Radiant barriers work with insulation but in a different way. Radiant barriers reflect hot air away from the living space.

Your greatest energy savings can come from combining both insulation and radiant barriers.

The reflective material on a radiant barrier is generally a thin film of aluminum bonded to a paper, plastic or cardboard substrate and comes in rolls or sheets.

Radiant barriers are easy for the DIY-er to install.

Tools, materials needed

Rolls of foil radiant barrier (48 inches wide by 125 feet long, or 500 square feet)

Staple gun

1/4-inch or 5/16-inch staples

Instructions

One method is simply to roll out the radiant barrier and lay it over the top of the insulation on the attic floor. This method is quick and easy. The one drawback is that the effectiveness of the radiant barrier is reduced when the reflectivity of the material is reduced. As dust collects on the reflective surface, the barrier simply will not work as well.

The other method is to staple the foil across the undersides of the rafters.

1. Start at the bottom and work your way toward the peak of the roof.

2. Overlap the foil 2 to 3 inches.

3. Staple the foil to the undersides of the rafters with the reflective side of the barriers facing the interior of the attic, not the roof.

4. Staple the foil in place at one end, and then move to the other end, stretch it taut and staple in place. The material is strong and can be pulled taut. You can then staple it to the rafters between the two ends, using three to five staples per rafter.

5. Cut around supports, ducts and other obstructions.

6. Leave a gap at the peak near the ridge cap to allow a hot air escape.

Rolls of radiant barrier cost around $70 for a 500-square-foot roll.