Aluminum reflects 97% of the radiant heat from the sun. However, the aluminum
will get extremely hot. For example, have you ever touched a foil-wrapped baked potato fresh out of the oven?
It will burn your hand. Instead, if you pick up the potato with a hot pad (insulation) the potato will not
burn the hand. The same holds true for an attic when the radiant barrier is not insulated. The surface
temperature of the aluminum will transfer into the attic, lessening the effectiveness of a radiant heat
barrier.
Attic Insulation
When the radiant barrier is properly insulated, the
surface temperature is transferred much more slowly. If given enough time, it will eventually pass into the
attic. Air does not convey heat effectively by conduction, therefore it is a good insulator.
The one inch of airspace combined with the one-inch thick polystyrene
will stop any measurable heat from entering the attic by conduction. One of the best ways to demonstrate the
effectiveness of polystyrene's ability to stop conduction of heat is to compare the temperature of coffee in a
metal cup against coffee in a foam cup...you can "feel" the difference.
Attic Ventilation
When the radiant barrier is properly insulated and
ventilated, the surface temperature will not have time to heat up the attic. The heat naturally moves upward
through a vented ridge system, effectively moving up and out before it can reach the attic. Ventilation is all
about proper location. The location of the soffit vents make a way for air to flow up and out of the roofing
ridge vent instead of entering your attic. By adding extra soffit vents, and with the help of the ThermaDeck
design, air is allowed to pass in and through a one-inch gap between the decking and the polystyrene foam
backing. This increases the flow of hot air transferred from the sun's radiant heat out of the roofing ridge
vent. Because heat naturally rises, with these holes in the proper place (within the 1" area), the air that
enters into the soffit vent will go straight through the holes to travel up and out of your roof (by
convection) without actually having to come into the attic space. With traditional attic design, air was
allowed to enter the attic. Although it certainly helped by moving air throughout your attic, something was
just missing. Billy couldn't accept the fact that the air had to enter the attic. He put his focus on keeping
the air outside where it belongs.
ThermaDeck Energy Benefits Explained
Watch as we show you just how effectively ThermaDeck holds up to a standard roofing system. We
not only have a demonstration, but it comes with notable research performed by the Oak Ridge
National Laboratory. Our patented roofing systems will not only last you a lifetime, they also come
with Financial Benefits.