Your Facility Could Benefit From Radiant Barriers
Summer sunshine on your commercial building will do more than simply raise the temperature in the area around the structure. Direct sunlight also heats up attic spaces and upper areas in the building, creating radiant heat that moves downward into your offices and other areas. Proper insulation can help, but the more effective solution is a radiant barrier.
The Nature of Radiant Heat
To understand a radiant barrier and what it can do for your facility, it is necessary to understand a little bit about radiant heat. When sunlight strikes the roof of your facility, the roofing material absorbs the energy in the sunlight, making it hotter. Heat, by its nature, will move from a warmer area to a cooler one. In this case, the heat will radiate away from the roofing material and downward into your attic or upper rooms. This can cause a dramatic increase in temperature in the spaces directly under your facility’s roof.
As the attic area gets warmer, the heat will move again, this time into the functional spaces below the attic. Offices, work spaces, storage areas, and other rooms below the hot attic will get warmer. Even large open areas such as gymnasiums or warehouses can be affected by this radiant heat.
Most often, these areas will become intolerably hot. If the area isn’t air conditioned, it will become too hot for anyone to work there for an extended period. Merchandise, raw materials, or other items stored in this area could be damaged or otherwise affected by the heat. If space is air conditioned, your HVAC system will work much harder to keep it cool, increasing your monthly cooling expenses and placing unneeded stress on the equipment.
What is a Radiant Barrier?
A radiant barrier is a layer of reflective material installed between the roof and the attic or other open space directly beneath the roof. These barriers usually consist of a layer of aluminum or other highly reflective material installed between the roofing material and the attic space. This material reflects radiant heat away from the upper areas of your facility, preventing the heat from moving downward into the attic and into the offices and work areas below.
The most common types of radiant barriers consist of a sheet of sturdy aluminum foil attached to a base of heavy paper, plastic, cardboard, insulation, or similar strong yet flexible material. The aluminum foil can be attached to one or both sides of the base. This type of reflective barrier is installed between the roofing material and the spaces directly beneath the roof.
Other types of reflective barriers consist of reflective material added to the surface of the roof itself. They can include reflective metal shingles, laminated roof sheathing, or reflective particles mixed in with the coatings on roofs.
The effectiveness of a radiant batter relies on three main factors:
- Emissivity: Also called emittance, this is the ratio of radiant energy put off by a surface compared to a black surface with the same temperature and area. Emissivity ratings fall between 0 and 1, with the most effective radiant barriers having an emissivity of 0.1 or lower.
- Reflectivity: The reflectivity, or reflectance, of a radiant barrier determines how much radiant heat it reflects. Reflectivity ratings are also between 0 and 1, with the best reflective barriers having a reflectivity of 0.9 or higher.
- Angle of installation: The angle at which the radiant barrier also affects how well it works. It should be perpendicular to the heat energy making contact with it–that is, the barrier will work best if it is at a 90-degree angle to the heat source.
Our goal is to help educate our customers about Plumbing, HVACR, Fire Protection, and Alarm Systems in Mechanical, Commercial, and Residential settings. For more information on using a radiant barrier to help keep your facility cooler, or to view projects we’ve worked on, visit our website!