Why Radiant Barrier?
This Question:
This question is really NOT does radiant barrier work? It's a proven technology -YES it works. NASA uses it, Frito-Lay uses it in their chip bags. Anyone who has a sunshield for their car windshield knows that radiant barrier works to reflect heat. The real question is HOW MUCH CAN I SAVE and IS IT WORTH the investment in my home?
As Far As Saving,
Let us illustrate two different homes and the related savings: We've stated you can expect realistic savings of 10%-20% with savings up to 35%. Another item is "Comfort". By reducing the radiant heat gain, your home will be more comfortable and it will FEEL cooler. Often, customers will raise their thermostats a couple of degrees to keep from getting too cool.
Remember - Radiant Barrier installed in an attic will ONLY reduce the heat entering from the ROOF.
The basic rule is that the more roof you have the more your potential savings.
House #1
One story 2000 square ft. "ranch style" home. If the house is 50' x 40' with 8' ceilings it has 16,000 cubic feet of space, 1440 square ft of WALL SURFACE and 2000 square ft of ROOF SURFACE. So the roof area (2000 sq ft) divided by the total surface area of the home (3440 sq ft) is 58% of the total "envelope". Because the roof represents such a high percentage of the thermal envelope it can have a very large impact on savings. In fact, we've got customers who have reduced their summer bills OVER 30% on very large one-story homes. As a one-story home gets larger, the percentage of roof to wall ratio increases. Some homes, (<4000 sq ft) can have the roof/ceiling represent over 75% of the thermal envelope.
House #2:
Two story 2000 square ft. "double layer cake style" home. If the house is 40' x 25' and 8' ceilings plus 2' between floors (total 18' tall) you have a total of 18,000 cubic ft. The WALL SURFACE area is 2340 square and the ROOF SURFACE area is 1000 square ft. Once again, take the roof area (1000 sq ft) divided by the total surface of the home (3340 sq ft) and the percentage the roof represents is only 29% of the total envelope.
Installing Radiant Barrier in a home like this will still be beneficial. However, the PERCENTAGE of savings will be less compared to the PERCENTAGE on the one-story Ranch Style home. But, remember the COST will only be half compared to the 2000 sq ft. home since you are only using 1000 sq. ft. of radiant barrier.
Hopefully,
This helps to explain why the percentage savings on the bills can vary greatly. Without going through and doing a complete heat load analysis it is difficult to really project the savings. Just remember, the more roof, the more POTENTIAL for savings. I'd still install it on a two story home with a small attic. It WILL reduce heat gain into the home which is very good. But, I would also try to plant trees to provide shade to the East/West walls too.
Radiant Barrier
Should be part of an overall strategy to make your home more comfortable and energy efficient. For most homes you should:
- Install Radiant Barrier
- Increase Attic Ventilation (Including Solar Fans & Soffit Vents if needed)
- Seal the ductwork
- Have A/C system checked and cleaned
- Air seal the home
Kathleen, GA
478-227-0428
Thomasville, GA