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Since you posted promotional content in a discussion forum, let's have some discussion....

Your web page claims your radiant barrier saves up to 35% on energy bills. That claim defies logic, since air conditioning typically represents less than 35% of annual energy consumption. Keep in mind that cooling loads from the roof only represent some fraction of the total cooling loads, and cooling is some fraction of the overall HVAC load.

Even in an extremely hot climate like Phoenix, roof-related cooling loads don't account for anything close to 35% of overall energy consumption, and radiant barriers obviously don't totally eliminate roof cooling loads, they just reduce them.

Indeed, according to a study done by the Florida Solar Energy Center, radiant barriers may save on the order of 8% to 12% of COOLING energy. Savings at the upper end of that range were found in homes with leaky ducts located in the attic, and poorly insulated ceilings (since the roof represents a larger portion of cooling energy). I would argue in that case that homeowners would get MUCH better bang-for-the-buck by sealing the ducts & ceiling and blowing more insulation.

At the other extreme, there was a large study of new Energy Star certified homes in Houston (all with energy code mandated insulation, air-sealed ceilings and ducts). A fair number of these homes had radiant barriers. The study showed that radiant barriers saved on the order of 3% of COOLING energy, which works out to less than 1% of overall energy.

These studies were done almost a decade ago. As energy codes and A/C efficiency standards evolve, savings potential from radiant barriers get even smaller. I used to specify Tech Shield (roof sheathing with factory-applied radiant barrier) in new construction in the hottest climates, but at 10-12 cents per sf upcharge over standard sheathing, even that small investment can't be justified when we move ducts out of the attic, as they should be.

Thanks David for weeding through the propaganda

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