Your actual savings will vary due to many different factors including: installation location, shading, air duct leakage, air handler location, geographic location, etc. In the South, you can expect to see a 40% reduction in heat gained through the roof, and this can translate into a 17% savings on cooling costs. Many independent studies and radiant barrier users have tested their results and reported energy savings varying from as low as 12% up to as high as 39%. Ra-flect™ radiant barrier reduces energy costs in both summer months and winter months because it is double sided, and will keep heat in during the winter months and reflect radiant heat away during the summer. Installing a radiant barrier in your attic is the most cost effective way of reducing your heating and cooling cost and providing the quickest payback of any energy efficient material or product.
While results will vary from climate to climate, attic installed radiant barrier will reduce heat gain through the ceiling by roughly 40%, which translates into a 17% average reduction in heating & cooling costs. The local climate and the installation technique chosen, will affect the performance of the radiant barrier, so be sure to choose the right installation for your local climate.
While this 17% figure holds true for many climates using a typical installation, it will vary from place to place. Many independent studies and radiant barrier users have tested their results and reported energy savings varying from as low as 12% up to as high as 39%.
Below is one such independent study in which the attic temperature of two similar neighboring houses where tracked over the course of one day. As you can see from the image below, the attic with radiant barrier(blue) performed quite nicely and stayed very close to the ambient temperatures outside(green) when compared to the house with no radiant barrier(red).
Factors Determining Radiant Barrier Effectiveness:
- Attic Ductwork – If ductwork or air handlers are located in the attic, the temperature of the attic area will affect the efficiency of the HVAC system. Using a radiant barrier to control attic temperatures will increase the HVAC system’s efficiency, thus reducing energy costs.
- Existing Insulation – If existing attic insulation is less than a R39, a radiant barrier installation will help to stop excess radiant heat. Homes with a R39 or higher ceiling-insulation, and have no ductwork in the attic will not achieve much energy savings from a radiant barrier installation.
- Cold Climates – In climates where the majority of annual energy usage goes towards heating the structure, a radiant barrier on the floor of the attic, above the insulation and ductwork will provide substantial energy savings.
- Hot Climates – In climates where the majority of annual energy usage goes towards cooling the structure, a radiant barrier stapled to the bottom of the roof rafters will provide maximum energy savings.
- Mild Climates – In more mild climates where neither heating nor cooling is used much, a radiant barrier installation will not create massive energy savings. However, the radiant barrier will increase the overall comfort of the structure while providing small to moderate energy savings.