Q&A / 

Radiant Barrier Chips Save Money

DEAR TIM: I have to do something to lower my heating and cooling costs. It can get very hot in the summer and my air conditioner runs non-stop. The winters can get bitter cold as well. I have added insulation in my attic and that seems to help but what else can I do? I have seen some radiant-barrier foils advertised as miracle products. Are these exaggerated claims? Is there a way to stop the heat from getting into my house in the summer and stopping it from leaving in the winter? Stephanie B, Minneapolis, MN

DEAR STEPHANIE: Wow! Talk about a complicated subject. Controlling heat loss and heat gain by creating a barrier that helps you lower your energy costs is not much different than a quest for the Fountain of Youth or the Holy Grail. But I may have shocking news. The map with the big red X may have been discovered. I believe I have uncovered a product that holds enormous promise for real long-term energy savings.

To watch the entire video, please Click Here .

Maintaining a comfortable interior climate in a home is a daunting task. This is especially true if you live in a part of the world that has weather extremes. For example, talk to a person who lives in the high desert of California or just about anyone in the Southwest and they will tell you how hot it can get on numerous summer days. Afternoon air temperatures above 100F are common. Attic air temperatures can soar to 145F or greater. If you want the inside of your home to be 78-80F, air conditioners can work long and hard to maintain the comfort zone you select at the thermostat. The same scenario is true in places that experience bitter cold temperatures for months on end.

When an object such as the sun, your furnace or boiler creates heat, it can radiate this energy in the form of infrared (IR) electromagnetic energy waves. This IR energy travels through space and in and around the inside of your home at the speed of light. The waves themselves are invisible and carry no heat, but when they strike a surface the energy begins to vibrate the molecules of the object. Those vibrations create friction which in turn creates the heat we feel when sunlight strikes our skin or when we touch an object that is warm or hot.

It stands to reason that if you intercept these IR waves with some type of barrier and simply bounce them back to where they originated, that the heat would not be transferred. An effective radiant barrier would indeed make your house much cooler as you reflected the heat back outdoors. This same radiant barrier would reflect the IR heat your furnace creates right back into your home.

This technology has been around for a very long time. Surely you have seen a cook wrap a hot dish with aluminum foil to keep the contents warm. Older thermos bottles have highly reflective coatings that keep liquids warm or cold. Firefighters use custom metallic foil suits to keep them cool. Our astronauts in space have special suits that have 17 layers of reflective material that keep them comfortable from extreme heat and cold at the same time. Radiant barrier materials work and they work well. The trick is making them work in a typical home.

The best radiant barrier products are the ones that have the highest amount of reflectivity. It only makes sense as they directly reflect more of the IR waves away. Anything that dulls the surface of the radiant barrier film significantly reduces its reflectivity. Many traditional radiant barriers for homes are foil laminates that can be stapled up in an attic or even laid flat on top of insulation. These offer only one layer of protection. They work well until they become covered with dust. As the dust builds up, their effectiveness goes down.

Two years ago, I had special radiant barrier chips installed in my attic. There are hundreds of thousands of randomly overlapping highly reflective foil pieces that bounce heat back to its source. In many places the chips may be ten or fifteen layers thick. I am not concerned with a dust buildup. The exposed layers I can see may get dusty, but just below are several layers that will always reflect the heat back to its source.

Those who build new homes have several additional options. Roof sheathing attached to roof trusses is available with built-in radiant foil on the underside. It would take years for that surface to become dust covered. You or your builder can buy drywall that has foil facing on the backside. This drywall can be used in all rooms that have walls or ceilings that are exposed to the elements. Of course, once the final attic insulation is installed, the radiant barrier chips I used can be installed to give the highest level of protection.

Column 447


One Response to Radiant Barrier Chips Save Money

Leave a Reply

Your email address will not be published. Required fields are marked *