R-value is a term used by the building and construction industry to define the thermal resistance a material has. The higher the R-value, the more resistance the product offers against heat transfer. Traditional insulation can vary vastly in the R-values it offers. The US Department of Energy has recommended R-values for certain areas in the USA, based on the general climate of an specific area. When combined with traditional insulation, there really is nothing better than radiant barrier to reduce heat gain in to the home.
That being said, many companies are selling radiant barrier with some form of insulation attached and claiming R-values of R-11 or more. The problem with these claims is that they are misleading to consumers and oftentimes the products only achieve an R-value of around 1. Consumers are paying about double the cost, for virtually no additional benefit.
So how can they make claims that these type of products (fiberglass sandwiched with foil or bubble wrap with foil laminated to it) offer an R-11 value? How does AtticFoil® compare to products like eShield and Prodex? The answer is in the fine print.
The bottom line is that if something sounds too good to be true – it just might be. Trust your gut and make sure you read the fine print. When looking to install a radiant barrier, you’re probably better off buying a pure radiant barrier and spending what you save on bulking up your traditional insulation if necessary. Consider your situation, and decide what is best for your home.