We Value Your Privacy

We and our partners use technology such as cookies on our site to personalise content and ads, provide social media features, and analyse our traffic. Click below to consent to the use of this technology across the web. You can change your mind and change your consent choices at anytime by returning to this site.

Update Consent
Loading ...

What Are the Causes of a Leaky Velux Skylight?

Updated April 17, 2017

Velux skylights, which bring cheery light into a room, are a popular choice in many homes, in both models that open and close and those with a fixed window. While considered one of the best of their type of product, Velux skylights occasionally can suffer from leakage. There are several reasons why leakage takes place.

Loading ...

Check the Roof Pitch

Up until 1996 or so, Velux recommended that its skylights be installed with a pitch of no more than 15 degrees, since increased to 18 degrees. New sealant may be needed, as well as longer screws to hold the skylight in place.

Sealant Problems

Sometimes, the sealant around the skylight may have cracked a little, allowing water to come in around the edges. A dab of roofing tar along the edges of the seal may stop the leak. If the seal as deteriorated too much, however, it may be necessary to chip it out all the way around the skylight, then apply a new bead of sealant.

Sash May Need Repair

Sometimes, the leak may be occurring around the sash of the skylight window, and a bit of caulking may be in order.


If the skylight appears to be sealed properly, check flashing near the skylight. Any nearby flashing, particularly if it is above the skylight, may lead water to flow down under the shingles and to work its way through thin cracks around the skylight that otherwise would be impervious to water.

When All Else Fails

If minor steps don't solve the problem, major ones may be needed. A reinstallation of the skylight may be needed--or a brand new skylight if the old one has deteriorated to the point it cannot be repaired. Such repairs may be beyond the skills of the average Joe Handyman, and you may need to consider a professional contractor.

Loading ...

About the Author

Greg Fish

Greg Fish has been writing professionally in Maine since 1987. He has reported and edited at "Lincoln News," "Advertiser Democrat" and the "Bar Harbor Times." Fish currently writes for the "Penobscot Times."

Loading ...
Loading ...