Reflective Roof Insulation Vs. Fiberglass Insulation

Reflective Roof Insulation Vs. Fiberglass Insulation

Between the immediate expenses of insulating material a roof and also the possible energy savings, the kind of roof insulation you choose can make a significant financial difference within the life span of your house. Reflective insulation and fiberglass work differently and one type may be better than another for certain needs, although neither is inherently, objectively better for roof insulation.

Basic Comparison

Fiberglass insulation is basically a thick layer of spun fiberglass full of tiny air pockets that trap air. Fiberglass roof insulation functions just like a blanket spread within your house, keeping thermal energy out throughout the summer and also keeping the heat in during the winter. Reflective insulation is made from aluminum foil backed with paper, cardboard or film. Where fiberglass insulation slows the transfer of heat, the aluminum in reflective insulation actually reflects heat away from itself.

Insulating Value

Most comparisons of unique alternatives for insulation evaluate the R-value, a numerical measure of how efficiently a type of insulation absorbs heat, of one material contrary to the other. However, reflective insulation does not absorb heat and isn’t granted an R-value for contrast. The U.S. Department of Energy reports that reflective insulation is the most effective at preventing back heat circulation, which makes it a better option for roof insulation where keeping heat out is always the most essential factor.


As of December 2013, a representative roll of fiberglass insulation acceptable for roof installation price 29 cents per square foot in a house improvement center. A comparable roll of reflective insulation price 43 cents per square foot in the exact same site. Though exact prices will vary by store and region, this price ratio is fairly consistent, meaning you may expect fiberglass to price about three-quarters the price of reflective insulation.

Ease of Installation

According to the U.S. Department of Energy, both reflective and fiberglass insulation are appropriate for do-it-yourself installation. Fiberglass insulation comes packed for easy installation between stud and joist spacing while reflective insulation comes from broader rolls. Reflective insulation is significantly slimmer than fiberglass insulation. Which is better will depend on the topography of the specific roof you are insulating.

Climate and Purpose

A Reflective Insulation Manufacturers Association International analysis of U.S. climates discovered that reflective roof insulation works best in areas with high sunlight and little cool weather. Areas where fiberglass insulation functions better comprise cold temperatures. The exact same study found the reflective roof insulation to under perform fiberglass rolls in a Mediterranean climate.

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