Why is my skylight leaking?

We are often asked the question, "Why is my skylight leaking?".

So, why is my Skylight Leaking? The cause is usually down to one of two things:

  • poor installation or
  • a build up of debris, usually around the flashings.

So lets look at the debris build up first. This is the simple one.

Skylights installed into tiled roofs can be prone to debris catching underneath the tiles. The leaves sit on top of the flashing and cause the rainwater to divert around the debris and over the flashing. With enough rain the water runs over the edge of the flashing and enters the roof cavity. The same issue can happen on a metal roof too, with the debris sitting between the flashings and the roof.

Regular maintenance will prevent this problem occurring. On a tiled roof, simply slip the tile off and clean the debris away from the flashing. Replace the tile and you’re done. It’s dead simple. On a metal roof, put your hand underneath the flashing and scoop out any debris from between the roof and the flashing.

Not so simple to fix is the poorly installed skylight.

Poor installation is the number one cause of leaking skylights. Time and again we see incorrectly installed Velux skylights. Installation recommendations are often overlooked or ignored. This can lead to a costly fix.

The best solution, of course, is prevention. Before starting, ensure you have a qualified and experienced skylight installer. Of course if it's already done, that's not much help. In this case the only action is to remove and reinstall the skylight.

Check out some of these examples we’ve seen this year already.