In some circles, skylights have a negative reputation. This reputation is largely due to the issues associated with their older, outdated, traditional design. If you are considering purchasing a daylighting system to help replace artificial lighting, here are a few reasons you may want to steer away from outdated options to prevent you from wasting money.
Issues with Weather Proofing
Many outdated or traditional designs were not created with sustainability and weather resistance in mind. Because of these design inadequacies and the risk from a poor installation, this makes cheaper solutions susceptible to problems including leakage. Leaks can cause condensation to gather inside the skylight, causing mold, rot, and other potential structural damage. Additionally, their flat-pane design increases the likelihood of developing ice dams, which can block the flow of light and leech heat from the building interior. Consumers should be sure to only purchase systems which have passed stringent AAMA weather resistance testing that confirms their resilience against high air and water pressure.
High Heat Transference
The design of traditional skylights most closely resembles horizontal windows, which creates a greater tendency to allow heat gain and loss than more advanced modern designs. Studies show that they actually admit four times as much heat than vertical windows, while allowing 35-45% more heat to escape the building envelope in cold weather. This can dramatically increase the demands on a building’s HVAC system. The National Fenestration Rating Council has established a rating system that reflects a system’s ability to prevent heat transfer. Consumers should compare these ratings for their daylighting options and purchase a system with a low SHGC and U-Value to ensure minimal heat transference and maximum thermal comfort.
Inconsistent Light Quality
Another major issue with traditional skylights is that they do not provide consistent light. The level of lighting they provide is dependant on the angle and location of the sun, which changes throughout the day. This causes huge fluctuations in the level and quality of light at different times of the day. Additionally, these outdated systems have a tendency to create bright spots below the skylight called pooling which creates glare. This kind of light is uncomfortable for the occupants and not can lead to repetitive eye strain as the eye struggles to adjust to changes in light, negatively affecting productivity. Consumers should aim to purchase a daylighting system capable providing consistent levels of fully diffused light. Studies show diffused natural light results in higher sales in stores, higher test scores in schools, and higher worker productivity in the workplace.
Reliance on Artificial Lighting
In addition to the issues mentioned above, traditional skylights are only capable of providing sufficient light for 4-6 hours per day, providing the best light only when the sun is directly overhead. This often requires turning on electric lighting during the remainder of the day, which reduces the savings the system can provide. Instead of relying on outdated daylighting systems, consumers should consider more advanced options. Some modern solutions are capable providing superior, fully diffused lighting for up to 10.5+ hours per day, and reducing energy use for lighting by 50-80%.