How does rFoil work?
Radiant heat, the major source of heat flow, is energy in the form of infrared waves. It is transmitted from a heat source -- like the sun, a heater, or even your body -- at the speed of light, through the air. A white surface, such as snow, reflects; a black surface absorbs it.
Typical insulation (such as foam and fiberglass), like most building materials, absorb a large percentage of radiant heat. However, tests have shown that rFoil reflects 97% of radiant heat. This means that it emits (lets through) 3%. But foam and fiberglass will block only 10% of radiant heat, which means it emits 90%.
To better illustrate this, look at the photo below. A piece of rFoil and a piece of R-19 fiberglass were placed under 250 watt heat lamps (radiant heat). After the lamps were on for nearly an hour, there was nearly a 30 degree difference in the two temperatures. This is because fiberglass can only slow heat down, not block it.
What is the R-Value of rFoil?
Single Bubble Foil, a foil/single bubble/foil lamination, is the most common kind of reflective insulation. We'll use this in our discussion.
A 1/4" piece of Single Bubble Foil has an R-Value of 14.3 in a ceiling application, and 9.8 in a wall application. 3" of fiberglass has an R-11, and 6" is an R-19.
But R-Value is a misleading number. R-Value only measures CONDUCTIVE HEAT (heat by physical contact), but remember, 90% of all summer heat gain and 75% of all winter heat loss comes from RADIANT HEAT -- heat that's transmitted from a heat source and moves through the air.
Since heat from the sun can overheat a building in the summer, and heat from a heater can escape a building in the winter, it makes sense to have an insulation that will actually block the heat, rather than slow it down. This is why rFoil works better than regular bulk insulation. When you're trying to keep heat out in the summer, or inside in the winter, fiberglass and foam just won't do it as well as rFoil. This is why R-Value is not always a good indicator of how well insulation works.
Plus, birds, rodents, and insects don't eat it, or steal it for their nests.
What other reflective insulation products do you carry?
There are three other reflective insulation products in the rFoil residential line:
And we're adding new products all the time. Be sure to check back to see what we have available.
How do I install rFoil?
It's easy. All you need are scissors or a utility knife, a ruler, and a straight edge (a 2x4 or 2x2 works great). If you're taping the seams (not necessary if you use No-Tear), use a plastic paddle or 4" block of wood to press the tape, and make sure it sticks.