For thousands of years people have been using skylights to bring light into their homes, churches, and businesses. Despite how old this technology is, it has taken a long time to develop. Most people's’ mental image of one probably looks fairly similar, a horizontal window in the roof of a building. Despite how common they are, these traditional skylights are far less effective than many modern technologies. Below are a few key reasons not to invest in outdated daylighting systems.
High Heat Transference
One of the common issues faced by traditional skylights is the fact that they allow a high level of heat loss and gain. Their horizontal window design absorbs solar energy, allowing the sun to heat a building interior four times as much as standard vertical windows. They also have a higher tendency to allow heat to escape—as much as 35-45% more than vertical windows. Do prevent this, search for a system with a low Solar Heat Gain Coefficient and U-value, ensuring minimal heat transference.
Location Reliant Design
Because of their design, outdated, passive skylights are highly dependent on the location and direction of skylights. In North America, North and South facing skylights will produce the least and greatest heat gain, respectively. On the other hand, Eastern and Western facing skylights will only provide viable light during one period of the day. Understanding how these issues interact can benefit a building’s lighting design, however, investing in a more efficient system which is not reliant on directional placement would eliminate the issue altogether.
One of the most common criticisms of traditional skylights is their poor insulation and weatherproofing. Whether this is an issue of installation or design, it makes these systems vulnerable to leaking. When condensation gathers inside of skylights it can cause mold and rot, as well as the potential of ice dams developing. Both of these situation can create severe structural damage, necessitating costly repairs. To avoid this, make sure you invest in a system which has been AAMA certified for weather resistance.
Because of their passive design, traditional skylights do not provide healthy, consistent light throughout the day. Because they admit light only when it passes directly through their lens, they can contribute to glare and light pooling. Both of these issues can create repetitive eye strain and stress-induced migraines. Additionally, this only allows these systems to provide adequate lighting for 4-6 hours per day, creating the need for supplementary artificial lighting.