Daylighting Renovations for Your Business
It's estimated that daylight harvesting systems has savings of 35 to 60 percent
If you've already started researching the possibilities of daylighting, you've probably discovered that experts agree that daylighting can save your business money, but nobody is exactly sure how much. The New Buildings Institute, for example, says that daylight harvesting systems can produce a maximum potential savings of 35-60%. But the Lighting Design Lab claims that lighting energy savings can reach 60-80% in offices, classrooms, and gymnasiums. Meanwhile, the U.S. Department of Energy takes a more inclusive stance, claiming that daylighting energy savings for interior illumination typically range anywhere from 30-70%. Naturally, these figures are skewed by any number of factors, including new construction vs. renovations for existing buildings, local climate, and specific implementation strategies. With this in mind, here's what you need to know and what you need to find out to determine if daylighting renovations make sense for your business.
The Big Daylighting Myth
As confusing and uncertain as daylighting statistics can feel, the biggest daylighting myth is that these lighting strategies only work with new construction. In truth, many buildings already have windows with sufficient openings and orientation to implement effective daylighting renovations. True, the most effective daylighting strategies are incorporated during the design and construction of a building, but too many business owners make the mistake of prematurely dismissing this solution without taking to a contractor.
Effective Daylighting Renovations
- Low-Glare Windows: It's easy to think that daylighting strategies use windows that let in the greatest amount of natural light, but this assumption is wrong. If employees experience a glare in their eyes or on their computer screens, the blinds will be closed shut, negating the daylighting strategy and cost savings. Typical window glass transmits 5,000 foot-candles of illumination on a sunny day and 1,000 foot-candles on a cloudy day. Most people need only 30-50 foot-candles to comfortably read. Thus, daylighting window design is about finding the right balance and angles to provide the most consistent, productive illumination possible for your business's workspace.
- Skylights: Though not for every business or every building, if your small business is located in a space with access to the ceiling, installing skylights or more sophisticated daylighting devices can create even more effective daylighting strategies. Research from the Institute of Energy and Sustainable Development conclusively demonstrates that energy savings created from skylights significantly overcome any energy loss created from decreased roof insulation. Moreover, tubular daylighting devices will allow greater versatility in illumination settings, while minimizing any degradation in insulation.
- Air Conditioning: In the summer, daylighting strategies are complicated by the fact that windows transmit heat as well as light through your window glass. If your business is still using incandescent light bulbs, this is already an issue for your air conditioning system. With fluorescent lighting, you may need to find ways to counterbalance this heat gain, especially if your business has windows that face southwest and can't be re-oriented. New double-paned, low-glare windows will already help considerably, but some businesses find that a new daylighting strategy is the perfect excuse to install a more energy-efficient air conditioning system.
Complete a Comprehensive Daylighting Cost Analysis
Needless to say, it's not easy trying to estimate the total cost and eventual savings of implementing a daylighting strategy. New windows may cost several hundred dollars a piece; a more efficient air conditioning system can cost several thousand dollars. The cost of installing a skylight is hugely dependent on your current roofing system. Yet, your business will also, more than likely, be entitled to tax credits associated with energy-efficiency renovations. If it's determined that you can save 20% or more of your lighting energy use, you may be entitled to a tax credit of up to $.60 per square foot for your business location. If, by also installing a new heating and cooling system, you can save 50% on your heating, cooling, and lighting costs, you may be entitled to a tax credit of $1.80 of your business's square footage.
The best way to complete a comprehensive daylighting cost analysis is to sit down with a qualified window contractor or daylighting specialist to discuss every aspect of the project. And with most of your business conducted during the day, if your utility company charges extra during the afternoon for peak-demand energy, greater savings will be realized with daylighting strategies. You should also consider the nature of your business operations, as some research suggests that daylighting will even improve workplace productivity and employees' health.