There’s no question about it: skylights are seen as being beneficial to any home because of their ability to bring in natural light. But you may not realize that they can have some serious negative impacts on a space or a whole building for a variety of reasons.

Benefit #1: Extra Daylight

One of the most positive aspects of having a skylight is that it brings extra daylight into a room, particularly during the winter months when days are shorter, there are fewer hours of sunlight, and the sun is at a lower angle than during the summer.

Benefit #2: Energy Savings

Because of this increase in natural light from skylights, the use of artificial lighting and electricity can be reduced, and during the colder months, skylights can contribute to the heat gain of a space and reduce the need for heating. Aside from the positive environmental impact that comes with using less electricity, the use of skylights has the potential to even reduce electric bills.

Benefit #3: Design Options

Another asset of skylights is their flexibility and range of design options, which can vary in location, size, shape, and angle so that they take advantage of local conditions. A skylight can be designed to capture early morning sunlight to help heat a space, but also so that it misses the strong afternoon sun that might make a room too warm. Some skylights come with shades or coatings to prevent overheating.

Benefit #4: Design Impact

Finally, skylights have the potential to either dramatically enhance a design or act as the main design feature in a space. Traditionally, they've been placed in spaces that were otherwise unable to have access to natural light through traditional windows, like the top of a staircase. However, they can also have the bonus effect of creating dramatic lighting and a sense of upward ascension that can still inspire designers today.

Drawback #1: Overheating and Over-Lighting

Though this abundance of rays can be a lifesaver in some spaces, it can also lead to potential problems related to bringing too much light and heat into your space. Make sure you keep this in mind when it comes time to decide on placement, size, direction, climate control, and how you'll be using the space.

Drawback #2: Heat Loss

Another issue with skylights is that they often lose heat during cool months. As a general rule, glass conducts heat better than other building materials like insulation or concrete, allowing heat from inside a home to escape to the outside. To combat this, homeowners should choose skylights that are thermally-broken (meaning that no piece of hardware or trim directly connects the outside to the inside), and that the glass is insulated.

Drawback #3: Installation Issues

Even if a skylight is insulated, there are frequently problems with sealing the shaft properly and making sure that it’s properly installed. All too often, a skylight isn’t correctly installed, leading to moisture problems and leaks that can not only drip into spaces below, but also spread leaks to other parts of the roof that were previously dry. What might have seemed like a minor leak could eventually lead to a much larger, complex issue.

Drawback #4: Cleaning Troubles

Finally, skylights can be tricky to clean. If you’re in the habit of spring cleaning and like to embark on the annual ritual of washing all your windows, you’ll probably find cleaning your skylights to be difficult, if not downright unsafe. To reduce the number of regular cleanings, you’ll want to make sure that they’re installed in areas where they aren’t likely to have leaves or branches falling on them, which would require frequent clearing or cleaning.

At the end of the day, a skylight—despite its flaws—can be a powerful design element and an important tool for incorporating daylight into a space. That is, so long as they're in a well-considered spot, have proper glazing, and have been installed correctly.