Everywhere you turn, it seems there’s a new option for energy efficiency that breaks the bank. As commercial building owners and facility managers weigh these options, bear in mind that the potential modifications available don’t need to rob your budget dry. JH Greene’s construction value engineering team often offers alternates in their proposals that uphold efficiency goals and can save up to 40% in annual energy costs. I had a coffee meeting with Tony Chase, JH Greene’s Director of Construction, and he shed some light on popular options that he’s seen several corporate clients turn to in recent contracts.
Petal to the Metal
A concept gaining some traction recently is the idea of a “cool roof.” There are several types of cool roofs, but one form producing some discussion is the metal cool roofing. As the sun’s radiation hits a roof’s surface, there is a high fraction of solar energy that is reflected by the metal, whereas asphalt roofs traps heat and absorb the energy. As reported by the Cool Metal Roofing Coalition and the Oak Ridge National Laboratory, “Installation of reflective metal roofing can save your home up to 40% in summer cooling energy costs while highly emissive metal roofs can reduce urban air temperatures by as much as 12 ° F. Combined, these benefits mean less money out of your wallet, less dependence on energy resources, and less general air pollution in your neighborhood and across the nation.” By controlling heat transfer, these roofs are designed to allow the least possible contact between the metal and the facility underneath. An added benefit is the easily recycled nature of the material at the end of its 30-year lifecycle.
Paint It White
If an owner doesn’t opt for a metal roof to deflect heat rays, white pigment layers can work in the same way with a thick coating that shields UV light and potential water/chemical damage. A Berkeley Lab delved into the concept a bit further to prove that white roofs offset CO2 emission drastically. It’s actually a requirement in California for building owners with flat roofs to have select white for the color. With the large portion of urban areas that encompass rooftops, this surface plays a large role in an area’s energy efficiency and from that, many programs are being launched on an international scale to instill these options and curb CO2 emission as much as possible.
Beyond the Surface
Below the immediate layer of roofing facing the elements, there are other factors that can cancel out any benefit of a “cool roof” if not properly addressed. An apparent issue is the additional strain placed on heating and air conditioning systems when a roof isn’t properly insulated. Green Home Guide points out that even if you do have insulation that seems adequate, it may not be doing the trick. To properly insulate a roof, the climate has to be a deciding factor in a building owner’s decision. Experts advise a variety of materials ranging from home foam insulation, cellulose insulation or even simpler choices like fiberglass or cotton batting. Author Amy Westerwelt points out that “No matter what material you choose, leaving an air space between the insulation and the roofing material is generally a good idea. Although in very dry climates, and with some metal roofing, it may not be necessary, an air space will typically reduce the possibility of moisture getting trapped in either the structure or the insulation and causing mildew or mold to grow.”
A building owner’s best choice is to engage an expert to ensure that all components are working together effectively. Whether a roof is undergoing initial construction stages, or a re-roofing project, these agenda items play a larger role than your electric bill—they can spur the health of the environment.