5 Reasons Why You Shouldn't Rely On Traditional Skylights
By Jeff Brain | June 22, 2017
In the history of lighting, skylights are one of the oldest and most relied upon forms of illuminating a building. Because of their long history, the skylight has seen many iterations over the years. Despite this, many people still insist on using skylights which employ a traditional flat-pane design. Below are a few of the issues this outdated skylight design faces, and why we hope people will begin to demand more out of their skylights.
1. Ineffective Weatherproofing
The criticisms which traditional skylights have rightfully been unable to escape is that they contribute to poor insulation and weatherproofing. Their window in the ceiling approach can allow snow or sleet to accumulate, causing harmful ice dams. Also, whether this is an issue of installation or design, these systems are extremely vulnerable to leaking. When condensation gathers inside of the skylights it can cause mold and rot, leading to severe structural damage, necessitating costly repairs. To avoid this, make sure you invest in a system which has been AAMA certified for weather resistance.
2. Susceptible to Heat Gain
The stationary, horizontal positioning of traditional skylights also contributes to greater heat gain. This is because your building receives the sun’s rays when it is directly above, at it highest and hottest place in sky. The incoming light heats the air inside of the building, elevating temperatures and requiring greater HVAC usage to keep the building comfortable. The U.S. Consumer Energy Center estimates that inefficient, outdated skylights absorb as much as four times the solar heat that vertical windows do, making buildings humid and expensive to cool in the summer months.
3. Break Building Envelope
Additionally, between air leaks and their horizontal design, these traditional skylights allow heat to escape from the building envelope. On average, they allow 35-45% more heat to escape a building than standard vertical windows. To avoid this issue, as well as excess heat gain, consider investing in a system with shades, sealed light wells, or other methods of preventing heat transference to keep costs low. Additionally, the National Fenestration Rating Council (NFRC) provides Solar Heat Gain Coefficient and U-value ratings for various skylight designs which can help predict the heat gain and loss they will generate.
4. Harmful to Productivity
While working under bright, diffuse natural light has been shown to both improve health and boost productivity. Working under lower quality light, however, can have the opposite effect. Many outdated skylights create light pooling leading to uncomfortable, uneven heat and light distribution. They also commonly generate glare, which can cause eye strain, even leading to migraines. These effects are so pronounced that when well-designed modern skylights are compared side-by-side with their older variations, the modern skylights increase productivity by 6-16% over the competition.
5. Inconsistent Light Source
Because older skylights have limited control over the light they allow into a building, allowing sunlight to pass directly downward through them into the building, the light they capture is inconsistent. This light often appear as bright spots on the floor that move across the space as the sun in the sky moves, preventing the space from appearing well lit, and disrupting the flow of the space. Not only that, while the best modern systems can provide up to 10.5+ hours of light per day, these skylights are only capable of providing 4-6. Consumers looking to avoid these issues should shop for skylight designs that produce diffused light and are designed to provide it for longer hours throughout the day.