are sky lights bad for your roof

Are Skylights Bad for Your Roof?

Allied Roofing Solutions has a long history of working on roofs and roof leaks.

Request a Free Quote

"*" indicates required fields

Your Name*
By submitting this form, you are consenting to our privacy policy and to receive text messages. Msg & data rates may apply.
This field is for validation purposes and should be left unchanged.

Skylights are good for letting the outside light in from above just as windows let light in from the sides around the room. A skylight–a glass window set into the roofline–has several benefits in making a room look larger and illuminating a space. But, in the past, they have had a bad reputation for causing leaks in the roof. There can be drawbacks that you need to be aware of, or the costs of repairs can be greater than the benefits. In this post, we will explore the pluses and minuses of skylights.

If you are concerned about a roof leak due to a skylight, please contact us to inspect the roof space surrounding your skylights to assess the health of the seals and make roof repairs if needed. A roof inspection will give you a clear and complete picture of the state of your shingles roof.


Can Skylights Cause Leaks in a Roof?

This is a common question about skylights. The answer is NO, not if they are installed properly. When the installation has been performed according to the manufacturer’s instructions, the likelihood of leaking is low.  If skylights are not installed correctly, you might experience leaks either immediately or down the road.

Replace a Skylight

When to Replace a Skylight

Just as there is with a roof, there is also an average lifespan for a skylight. Usually, a skylight will last between eight and 15 years. After that length of time, it needs an inspection to see that the seals, caulking, and surrounding shingles are holding up. Technology has improved such that many skylights can last up to 20+ years. And, it’s important to note that you need to maintain your skylight to keep it performing at its best. Keeping an eye on your skylight during and after storms to check for damage as well as cleaning it inside and outside will ensure you get many years out of it.

Benefits of Skylights

Adding Natural Light

Skylights allow natural light to enter your home more abundantly than when you only have windows in a room. This is advantageous when you have a room that isn’t situated in the most optimal location to get light.

When properly selected and installed, skylights can help minimize your heating, cooling, and lighting costs. Skylights can:

  • Offset the cost of lighting during the day
  • Provide a source of ventilation for hot, moist air, such as steam from a shower or heat radiating from an oven
  • Add solar heat to a chilly room

An attic may be a good place to have a skylight. An option that is gaining popularity is Ventilating Skylights. Ventilating skylights work by drawing fresh air into a room through a small opening at the bottom of the skylight. The hot air and moisture in the room then escape through an opening at the top of the skylight.

A skylight can make a space seem larger. This benefit can be useful in a loft, for example, that is being used as a family room or bedroom.

Because skylights bring natural light into a room, they can create positive feelings and attract people who are looking for that kind of relaxing interior home environment. Skylights add tremendous value when compared to the investment you make in them.

Drawbacks of Skylights


It is a big misconception that skylights always leak. They don’t. Skylights have the potential to leak simply because they are penetrating the roof but if they are installed properly, they shouldn’t leak. There are three reasons why a skylight can leak.

  • The installer didn’t follow the installation instructions. If you have no leaks during the first rain after the skylight is installed, then you know the installation was done properly.
  • The skylight needs to be replaced. Many skylight manufacturers have no-leak guarantees for up to 10 years. If your skylight is around 20 years old, it is getting to the end of its lifespan for the materials to fail and for leaks to start occurring. If you are replacing your roof, it may be the perfect time to get new skylights.
  • The skylight is defective. It is very uncommon for a skylight to have manufacturer defects. There can be a problem with the seal, flashing kit, framing, glass, or something else. When this is the issue, you must contact the manufacturer to get a replacement. Your roofing contractor can document the defect and give you an explanation to communicate to the manufacturer. If it is determined that the skylight is defective and wasn’t damaged or improperly installed, there should be no problem in getting it replaced.

Skylights transfer heat to the surrounding roofing material, which causes snow that has accumulated to melt. In turn, ice dams can form when the water refreezes. An ice dam forms at the edge of a roof and prevents the melting snow from draining off the roof. When this occurs the water backs up behind the dam and can then leak into the house and cause damage to walls, ceilings, and insulation.

You can end up with a room that is too bright, depending on the orientation and the size of the skylight. It’s possible to end up with a room that is practically unusable at certain times of the day. To avoid this issue, keep the skylights on north-facing roof sections if possible. Facing north limits the amount of direct light that comes from the skylight. If it isn’t possible to locate the skylight on a north-facing roof, put it higher on the roof to take advantage of a longer skylight shaft. If these tactics aren’t feasible, you may need to use shades or blinds or get rid of the skylight altogether.

Windows and skylights can be a thermal liability by causing a room to get too hot in the summer or too cold in the winter. Be sure to look at the specifications for the skylights you are installing or already have.

Suggestions to Maximize the Benefits of Skylights

  • Install skylights in climates that don’t get too hot in the summer.
  • Install skylights on the north-facing roofs, if possible.
Benefits of Skylights

  • Install skylights where they get shaded in summer.
  • Install high-quality skylights with the best specifications. This means double- or triple-pane with U-factors and solar heat gain coefficients well below what the code requires.
  • Eliminate skylight shafts or make sure they are insulated and air-sealed.
  • Use the best water management materials and methods you can to reduce the risk of water leaks on the roof.

Contact Allied Roofing Solutions for All of your Roofing Needs in New Jersey

If you are experiencing leaks around existing skylights or if you are putting new skylights in, contact our team at Allied Roofing Solutions. We can inspect your roof for potential problems around skylights and other vulnerable areas. Our team of professional roofers is knowledgeable and able to diagnose leaks quickly. Contact us to schedule a free estimate. We serve New Jersey residents in Bergen County, Essex County, Hudson County, Middlesex County, Morris County, Passaic County, and Somerset County. Call us at  (201) 773-0633 or complete our easy-to-use contact form to schedule a free estimate. Let us help you protect your home from roof leaks in the wet weather.