Reduce Cooling Costs in Multifamily Homes with Radiant Barrier Sheathing

By David Nelson, P.E., market support engineer, iLevelEnergy efficiency is a top priority for many multifamily builders and developers when planning projects. Features such as energy-efficient windows and appliances can be key selling points with renters and condo owners. Going another step, the choice of roofing materials can further boost energy savings. Radiant barrier sheathing (RBS), for example, provides a simple, cost-effective way to reduce energy use while helping ensure strong and long-lasting roof framing. Roofs built with standard sheathing allow solar energy to penetrate through it, heating up the air in the attic space. The heated air can then filter through the insulation into living spaces, causing room temperatures to rise. More energy is needed to cool rooms, resulting in higher energy costs.   Radiant barrier sheathing reflects solar energy away from the roof with a radiant foil layer, reducing the amount of heat that is transferred from the attic into living spaces. Less energy is needed to cool housing units, helping reduce energy costs and helping lower greenhouse gases from energy usage.Radiant barrier sheathing contributes to lower energy use by reflecting up to 97 percent of the sun’s radiant energy. It works in conjunction with the structure’s insulation to help keep apartments cool. For condominiums, duplexes or attached homes, the sheathing can also help keep un-insulated and un-air-conditioned rooms such as porches, garages, and workshops cooler, increasing usable space.Radiant barrier sheathing also offers other benefits. It helps to put less strain on attic-mounted appliances and ductwork by keeping attics cooler. The sheathing, made of oriented strand board (OSB), also is engineered to remain flat and resist buckling, cupping, warping and sagging. These properties help provide a smooth roof and reduce the risk of costly and time-consuming construction call-backs. Plus, RBS installs similar to other roof panels and does not require additional tools, labor or materials.  Builders and developers can use RBS as a simple way to differentiate themselves from the competition and support the growing interest in green multifamily construction.  Using radiant barrier sheathing is a small step toward green building goals that can have a positive, significant impact on energy performance. David Nelson, P.E., is a market support engineer for iLevel by Weyerhaeuser.