What Is Radiant Barrier Reflective Insulation?
Radiant barrier
insulation is a reflective insulation system that offers a
permanent way to reduce energy costs. Radiant barrier
insulation systems reflect radiant heat energy instead of
trying to absorb it. A pure aluminum radiant barrier
reflective insulation is unaffected by humidity and will
continue to perform at a consistent level no matter how humid
it may be. A radiant barrier insulation system is a layer of
foil facing an airspace and is installed in the envelope of a
building.
Most people are
familiar with traditional insulating materials such as
fiberglass, cellulose, Styrofoam, and rock wool. These
products use their ability to absorb or resist (slow down)
convective and conductive heat transfer to insulate (R-value).
A third, seldom discussed but dominant form of heat transfer
exists: radiant heat transfer. What
are the differences among the three forms of heat transfer?
 Conductive: Direct contact. If you touch a pot
on the stove, this is conductive heat transfer.
 Convective: Steam, moisture. If you put your
hand above a boiling pot, you will feel heat in the form of
steam. This is convective heat transfer.
 Radiant: Electromagnetic. Step outside on a sunny day and feel the
sun’s rays on your face. You are feeling radiant heat
transfer. All objects above absolute zero (-459.7 degrees F.)
emit infrared rays in a straight line in all directions.
A radiant barrier reflects
radiant heat energy instead of trying to absorb it. What does
this mean in your home or business? During the winter, 50-75%
of heat loss through the ceiling/roofing system and 65-80% of
heat loss through walls is radiant. In the summer, up
to 93% of heat gain is radiant. If you are
depending on R-value (resistance) alone to insulate against
heat gain and loss, remember that thin layers of fiberglass are virtually transparent to radiant energy and are
affected by changes in humidity (moisture levels). A 1-1/2%
change in the moisture content of fiberglass insulation will
result in a 36% decrease in
performance (referenced from HVAC Manual 10.6; McGraw-Hill). A
pure aluminum radiant barrier is unaffected by humidity and
will continue to perform at a consistent level no matter how
humid it may be.
Testing and Approvals
- Building Officials and Code Administrators
- International Conference of Building Officials
- Southern Building Code Congress International
- Metropolitan Dade County (FL) Building Code Compliance
Dept.
- United States Testing Company
- Tennessee Valley Authority
- Tennessee Technological University
- State of California
- Oak Ridge National Laboratory
- Texas A & M University
See the Radiant Barrier reflective insulation products we have to offer.
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