What is Radiant Barrier?
Also commonly known as reflective insulation, radiant barrier features aluminum foil with a variety of backings such as cardboard, roof panels, plastic, and much more. The resistance to heat flow depends on the direction of heat flow with this type of insulation. Radiant barrier is most effective in reducing downward heat flow. Technicians usually place radiant barrier systems between roof rafters, floor joists, or wall studs. Reflective insulation can also be placed in walls or on the attic floor, but the material requires piercing to allow water vapor to pass through it.
How Radiant Barrier Works
Heat travels from a warm area to a cool one by a combination of conduction, convection, and radiation. Heat flows by conduction from a hotter location within a material or assembly to a colder space. For example, when you place a spoon in a hot cup of tea, the hot tea conducts heat through its handle to your hand. Convection heat transfer occurs when a liquid or gas is heated, becomes less dense, and rises, such as air. Radiant heat travels in a straight line away from any surface and heats anything solid that absorbs its energy, thereby creating about an extremely hot attic space in your home.
The insulation material we use works by slowing down conductive heat flow and convective heat flow. Radiant barriers work by reducing radiant heat gain but must be installed in a manner to minimize dust build-up on the reflective surface. Dust build-up will reduce its reflective capability. The reflective surface must face an air space to be effective and works best when it's perpendicular to the sun's radiant energy that is what is making the roof hot. Much of this heat travels by conduction through the roofing materials onto the cooler attic surfaces, including the air ducts and the attic floor.
The higher the temperature differences between the sides of the radiant barrier material, the greater the benefits a radiant barrier offers.
Installation of radiant barriers is more efficient and effective in hot climates, especially when cooling air ducts are in the attic. Some studies show that radiant barriers can reduce cooling costs by 5% to 10% when used in a warm, sunny climate. The reduced heat gain may even allow for a smaller air conditioning system.
Radiant Barrier Installation
Due to the fact that radiant barrier's effectiveness highly depends on proper installation, this is not a DIY project. It is best to use a certified installer for greater energy efficiency results. A professional will install your radiant barriers utilizing necessary safety precautions and according to local building and fire codes.
At Attic Control, our professional installers will ensure that proper air space is applied between the attachment points and that it is installed in a manner to minimize dust accumulation on the reflective faces.
It should also be noted that reflective foil will conduct electricity, so workers and homeowners must avoid making contact with bare electrical wiring. This is an extreme precaution. It should also be noted that if installed on top of the attic floor insulation, the foil will be susceptible to dust accumulation and may trap moisture in fiber insulation, so it is strongly recommended that you NOT apply radiant barriers directly on top of the attic floor insulation.
An Attic Control professional will be more than happy to provide you with a free estimate today! Call us now to book our next available appointment!