Frequently Asked Questions
What is a Radiant Barrier?
Radiant Barrier is a layer of Reflective Foil Insulation that is placed in an air space to block Radiant Heat Transfer between a heat radiating surface and a heat absorbing surface.
How can a Reflective Foil Radiant Barrier benefit me?
A Radiant Barrier can block up to 97% of radiant heat from being transferred.
What is the R-Value of Reflective Foil?
R-Value refers to the “Resistance” of heat flow through an object so we cannot accurately use this method to compare Reflective Insulation and conventional insulation such as fiberglass and cellulose. This is because Reflective Insulation completely reflects/blocks heat flow, it doesn’t absorb or resist it, thus giving reflective radiant barrier systems superior performance.
How well does Reflective Foil work compared to fiberglass insulation?
Reflective Foil will stop or reflect 97% of Radiant Heat Energy. Radiant Heat is often overlooked and misunderstood because R-Values do not take it into account. Radiant heat transfer is responsible for up to 75% of the total heat gain or loss in a structure. Traditional insulation products such as fiberglass, cellulose and foam board are effective in reducing CONVECTIVE and CONDUCTIVE heat transfer but are very ineffective against RADIANT heat transfer.
What is RADIANT heat?
Simply stated, it is heat energy that is radiating through an airspace. If a surface is hotter than an adjacent airspace it will emit that hot energy (in the form of heat rays) into the airspace. These heat rays are invisible but powerful.
Are foil radiant barriers the same as standard household aluminum foil?
Standard aluminum foil (ie. Reynolds Wrap) is not the same as a reflective foil radiant barrier. Standard household aluminum foil is a very thin sheet of aluminum mixed with other alloys that will oxidize over time, and has virtually no tear-resistance. Radiant barrier foil has a multi-layer structure, and is reinforced with a woven scrim that provides outstanding tear and tensile strength. Radiant barrier foil also contains a much higher aluminum content for greater reflectivity, and is coated for durability and corrosion-resistance.
I already have fiberglass insulation on my hot water tank. Do I need a Radiant Barrier?
Fiberglass and cellulose insulation work by slowing down heat transfer from one source to another. That’s why the thicknesses of those insulations are crucial for performance. Also, fiberglass and cellulose only resist heat transfer, they don’t block or reflect it so it eventually escapes through. A Reflective Foil barrier can be installed over top of existing insulation to form a reflective cover to enhance your other insulation.
How does reflective foil insulate if it is so thin?
It’s a common misconception that insulation must be thick to perform well. A thicker insulation will always have a higher R-value than a thinner insulation but R-value does not measure all heat transfer. It’s highly possible for a thinner reflective material to provide better thermal performance than a thicker non-reflective product with a higher R-value.