Radiant Barrier Attic Rafters
The hot roof material then radiates its gained heat energy onto the cooler attic surfaces including the air ducts and the attic floor.
Radiant barrier attic rafters. A radiant barrier works best when it is perpendicular to the radiant energy striking it. When a good radiant barrier is employed under the attic rafters directly before the sheathing decking new construction or along the bottom of the rafters preexisting construction a majority of the heat is reflected back through the roof and never enters the attic at all. A radiant barrier reduces the radiant heat transfer from the underside of the roof to the other surfaces in the attic. Radiant barrier installation attic radiant barrier installation most of the heat entering a home comes through the roof.
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 barriers are utilized to reduce summer heat gain in attics. A radiant barrier applied horizontally over the attic floor insulation is the more popular application for existing homes in cool climates. The heat escaping in the winter will be blocked at the insulation level while heat radiating down in the summer will still be blocked from reaching the living space.
For really high roofs you should consider doing a flat top installation for radiant barrier for tall attics. A radiant barrier combo installs radiant barrier on the attic rafters attic floor over your existing insulation and or attic floor plywood decking exterior facing vertical walls and interior facing vertical walls. Radiant barrier paint performed the worse providing a heat decrease in the conditioned space of around 19. Radiantguard radiant barrier foil insulation installed in an attics can reduce attic temperatures by up to 30 degrees when stapled with a staple gun to the underside of roof rafters by reflecting up to 97 of the radiant heat that strikes its surface thereby reducing heat.
Attic area of 55 x 35 1925 sq ft x 1 3 for a medium pitch roof about 8 9ft high at peak 2 503 sq ft. So you would order 2 500 sq ft of atticfoil to cover an area this size. The results were very telling. A control study was published in 2013 showing the radiant barrier effectiveness of paint foil backed sheathing and foil that was stapled onto the rafters.