Homes that depend more on skylights in combination with vertical windows to provide adequate levels of daylight tend to be more energy efficient, according to a study commissioned by VELUX America.
“A Study of the Energy Impacts of Residential Skylights in Different Climates,” prepared by Group14 Engineering, used computer models based on a 1-story, open plan, single-family home modeled under code-compliant conditions of California’s Title 24 regulations (California Energy Commission, 2008), Residential Package D. The baseline-modeled home has a maximum 20 percent window-to-floor area (with no skylights) with windows evenly distributed on all facades to achieve an average daylight factor of 5 percent.
Researchers added skylights and adjusted the amount and configuration of vertical windows to test how the model would perform in different climate zones, while giving the living space sufficient daylight to allow lights to be switched off. The study explored the effects of these configurations on the utility bills generated by the model homes in Los Angeles and Napa, California, and then expanded the models to Boston, Chicago, Denver, Dallas, Minneapolis, Orlando and Seattle, using their specific code requirements.
It found that by providing daylight from above via skylights, the total fenestration area could be reduced from a maximum 20 percent of floor area to as low as 12 percent of floor area while achieving the same baseline average of daylight factor target of five percent.
This was found to reduce annual heating and cooling energy use and costs in all but two of the 108 models with skylights that the group analyzed. Lighting savings, shading efficiencies, and increased natural ventilation attributable to skylights were not evaluated for simplicity. Further studies are planned to look into quantifying these additional efficiency contributions.
“While we have always known the intangible benefits of adding daylighting from above to homes, this study provides empirical evidence that natural light from skylights can contribute to the home’s overall energy efficiency,” said Stephan Moyon, direct of sales for VELUX America.
An in-depth discussion of the study, as part of a GreenExpo365 webinar titled “How To Reduce Energy Use By Improving Daylighting,” is available online. The full study report is available from VELUX upon request. VELUX continues to study and document the role and effectiveness of skylights in providing daylighting and passive ventilation.
VELUX America has produced three informational and instructional videos, none longer than three minutes, for roofing industry professionals. Topics include skylight replacement profit potential and customer benefits, skylight selection and skylight installation. The videos feature ENERGY STAR-certified VELUX Solar Powered Fresh Air Skylights and explain the advantages of skylight replacement or new installations during scheduled roofing work from the roofer and customer perspectives. The videos also explain the 30 percent federal tax-credit eligibility for the homeowner on product and installation costs, as well as solar-powered blinds.
The new VELUX SunCurve, a highly transmissive light capturing technology for commercial SUN TUNNELS, captures more morning and evening daylight while diffusing the powerful afternoon sunlight to provide a more even and appealing light output throughout the day. Another key improvement to both the residential and commercial products is the Flexi-Loc tunnel assembly system that will enable installers to save approximately 50 percent of the time required for tunnel assembly while making quick, easy, and adjustable connections.
ThA new diffuser complements any décor with a choice of brushed nickel, polished brass, oil rubbed bronze, and white trim options. Manual blackout shades and night light kits are available for various SUN TUNNEL residential skylight models.
A new commercial SUN TUNNEL ordering system allows for configuring and ordering exactly what is needed, or for larger projects, in bulk, for cost savings from an extensive selection of new options and accessories.
Commercial ceiling options include hard, suspended and open while diffuser options include frosted for aesthetics, prismatic for a look and feel to match existing architectural design, and Fresnel to maximize light distribution.
This completely redesigned touchscreen unit is powered by VELUX INTEGRA to operate VELUX electric and Solar Power Fresh Air Skylights and blinds. It is easier to program and use and comes with pre-set programs that automate commonly used functions of the skylights. The touch-sensitive screen utilizes easily understood icons and is extremely user friendly.
VELUX Solar Powered Fresh Air skylights, along with solar-powered blinds operated by the new remote, plus installation costs, are eligible for a 30 percent federal tax credit. VELUX is an ENERGY STAR partner and has been recognized as a Partner of the Year.