The addition of a skylight in any room of your home not only provides natural light and brightens the space, but it adds an architectural element as well. There are even skylights that can be opened to provide air flow, especially handy in a room where there are no exterior walls for a window.


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The biggest complaint of people who have a skylight, though, is that they can leak if not installed correctly. This can turn all of the positive traits into a nightmare situation as a leak can cause problems like insulation damage, mold, and eventually structural deterioration.

One of the main culprits is that the weatherproofing or flashing around the skylight is damaged due to deterioration or has been improperly installed. Flashing is used to prevent water from seeping into a junction of your roof with another surface feature such as a chimney, vent pipes, along walls, and, of course, skylights.

This post offers an explanation as to why a skylight might leak:

Why do Skylights leak? |

With different types of roof pitches and style of roofing materials are used, the skylight flashing has to be right for the application or you have the possibility for a leak, when a rain storm hits. When using shingles, shakes and slate type materials, a upper and low saddle with step flashing is the rule of thumb. Tile with a profile uses a lead upper and lower saddle, then a pan flashing down the sides. Low slope roofs can use a solid flashing { no steps } or cant strip at the base of the curb, with the low slope roofing sealed at the corners and rolled up the curb. In most cases a fixed skylight flange will cover the metal or roofing, making a good water proof skylight.

Read more here:  Why do Skylights leak? |

Skylight Flashing

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That’s a pretty technical description of how to properly install flashing, but the point is that you have to know what you’re doing when putting in a skylight. Usually you are best to consult with a reputable Denver commercial roofer to do the job.

However, if you want to try your own repairs and feel safe being on your roof, first you need to figure out where the leak is. Chances are good that the problem is the seal between the flashing and the roof.

When fixing a leaky skylight, you may need a couple adhesive products: roof cement and clear silicone caulking. Use the roof cement under the flashing as close as possible to where it meets the roofing felt.

Seal up any obvious holes or open seams in the flashing with the same product. Then, clean along the area where the skylight glass meets the frame and use the clear silicone caulk to seal that area.

If you are still experiencing leaks, you may have to replace your skylight, which is shown in the next video:

At 3:40, he shows how to flash the window to make it water tight, which we mentioned is the usual offender of leaks. Managing the step flashing and counter flashing makes the skylight sealed and waterproof.

If you are planning to have a skylight and want to know what type of cost to expect, the prices vary depending on the area. The following graph from Home Advisor shows the average price as well as the potential low and high amount.



If you want to know the price to expect in your specific zip code, you can enter it in the above graph. Choosing the right skylight for your home is part of the equation, as there are three main types:

  • Fixed Skylights
  • Ventilating Skylights
  • Tubular Skylights

Each has it’s own unique features, but tubular is the most affordable option. One thing to keep in mind is that all require more materials than just the skylight, as you will need lumber, drywall, paint, as well as some roofing materials.