Roof Radiant Barrier Under Shingles
The temperature of the attic space increases and that heat is transferred to the building below.
Roof radiant barrier under shingles. However we will do our best to explain why the effect is nominal. Attics heat up when the sun s radiant energy heats the shingles and the heat is transferred to the interior attic space through the roofing materials via conduction. Radiant heat travels in a line and heats anything solid within its path. Roofingfoil underlayment is designed to go on top of the roof deck and is an underlayment product and radiant barrier all in one and is an excellent choice for metal and tile roofs.
There are a number of ways a cool roof can be created including the installation of radiant barriers within the attic as well as radiant shingles on top of the roof. There is a misconception that if the heat is coming in through the roof shingles and strikes a radiant barrier only to reflect back out of the roof shingles then it will be twice as hot. In these attic space applications there is an air space below the radiant barrier. Roofing material warranties are not affected by the installation of radiant barriers.
A radiant barrier can be effective with an asphalt shingle roof only when installed inside the attic either to the underside of the roof decking or to the underside of the roof rafters. This can be a little tricky to understand because it seems logical that the roof would get hotter if the radiant barrier below it is reflecting 97 of the radiant heat back through the roof assembly. When the sun heats a roof it is the sun s radiant energy that makes the roof hot. The florida solar energy center also conducted a study on the use of radiant barriers under shingle roofs and found that properly installed radiant barriers do not void the warranty for the shingles.
Increasing summer energy consumption and cooling costs. April 19 2019 posted in. You can install the radiant barrier foil below the raised shingles either on top or below the battens. Radiant barrier applied either under the roof rafters or under the roof sheathing is probably the most common application of a radiant barrier but many homeowners shy away from it because they don t fully understand what radiant barrier is or how it works.
Radiant barrier under shingles scams bad information foil under shingles will not create a radiant barrier unless there is an airspace on one side of the foil. At first it sounds reasonable. Radiant barrier damages roof shingles. If the roof deck sheathing is installed with the radiant barrier facing into the attic space the radiant barrier must be perforated.