Cool air is passive, but heat is always on the move in your home. Installation of a radiant barrier can slow it down. Heat rises, transfers through ceilings and walls, or radiates from a hot surface to a cooler one. Plugging air leaks can prevent heat loss from living spaces due to convection in winter. Adding insulation reduces downward conduction from a hot attic in summer. But heat from the sun’s energy radiating through the roof and into the attic can only be reduced by radiant barrier material.
A radiant barrier is a thin, reflective material such as aluminum applied to one or both sides of another material such as paper, plastic film or cardboard. Radiant materials may also be built into roof shingles or roof sheathing installed in new construction or during installation of a new roof.
Radiant barrier retrofits are usually installed by draping the barrier face down in the attic under the entire span of the roof, stapled to roof joists. This reflects radiant heat back toward the roof. The barrier may also be laid atop beds of existing insulation on the attic floor. However, dust accumulation in this configuration will degrade the barrier’s reflective properties over time.
Energy savings from reducing radiant heat are most distinct in hotter climates like here in Fresno, where cooling costs may be reduced 5 to 10 percent. Radiant barriers cut costs in three ways:
- By repelling heat radiating through the roof, barriers reduce the amount of radiant heat that continues downward into the ceiling and living spaces.
- Less radiant energy entering the attic also means less heat build-up, reducing the amount conducted through the ceiling into the home.
- Air conditioning ducts are frequently routed through the attic. Because the cool surface of ductwork accelerates radiant heat exchange, installation of a barrier decreases thermal loss from ducts in the attic.
With nearly 40 years of sales and service to Fresno area homeowners, Donald P. Dick Air Conditioning sets the standard for interior comfort and customer satisfaction. Let us show you how we’ve built our reputation.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about radiant barriers and other HVAC topics, download our free Home Comfort Resource guide.