One of the most common questions asked by people interested in installing energy efficient skylights is simple: “What effect will a skylight have on the temperature of my building?”
Older skylights, particularly those in early 20th century buildings, were often made from untreated glass. As a result, just like windows, they resulted in a massive heat increase in the rooms in which they were installed.
Today’s skylights, however, have a wide variety of glazing and insulation options to choose from, many of which significantly reduce the amount of heat that they allow to travel into your room from outside.
Skylight position and heat transfer
Skylights are designed to let in light, but not necessarily heat. One of the biggest and most important factors in determining your skylight’s effect on interior temperature is its position with your building.
When a skylight is installed on a north-facing roof, it typically lets in steady levels of light without a significant increase in heat. This is because north-facing skylights are constantly exposed to light, but never directly exposed to solar radiation.
Skylights on east-facing roofs tend to let in large amounts of light and heat during the morning. Likewise, west-facing skylights let in heat and light in the afternoon, due to the movement of the sun from east to west throughout the day.
While north-facing skylights allow steady light with little heat gain, a south-facing skylight allows stable and steady levels of light and heat to enter your workplace, assuming it isn’t glazed or insulated to prevent heat transfer.
Another factor that affects your skylight’s ability to prevent heat transfer is its slope relative to your latitude. A low slope allows more exterior heat to enter the inside of your workplace in summer and more to escape in winter – not a good combination.
Your skylight manufacturer will be able to provide more information on the perfect slope for your location and requirements, as the ideal slope for your skylight ranges based on your latitude and its position within your building.
Skylight glazing and heat transfer
Today’s skylights aren’t the simple sheets of glass that they once were. Instead, they are treated and glazed using a variety of materials designed to reduce UV exposure, heat transfer and environmental wear.
One of the biggest positive effects of skylight glazing is its ability to reduce the level of heat that travels into your home from outside through your skylight. Glazed glass gives you all the light with significantly less heat gain and heat loss.
Many of the glazing materials used in today’s skylights are designed to reduce ultra-violet radiation and heat transfer. Some skylights are even glazed using special tints that absorb heat and prevent your workplace from being uncomfortably warm.
Finally, some glazed skylights use a special insulation material that’s fitted between the sheets of glass to prevent heat transfer. With the right glazing, your skylight can let in healthy, productivity-inspiring natural light without adverse effects on heat.
Should you be concerned about heat?
For the most part, no. Although early skylights were notorious for creating hot and uncomfortable interior spaces, today’s skylights are available with a wide variety of glazing options to prevent unwanted heat transfer from affecting your workplace.
From adjusting the placement of your skylight to let in light but not heat to simply selecting a skylight that’s glazed and insulated to prevent heat transfer, there’s no shortage of ways to make sure your skylight lets in light without unwanted heat.