Skylight leaking – How to make repairs.
When a skylight is leaking, most of the times the flashing is what cause the leak. On a shingle roof, the flashing comes in small pieces that are layered with every row of shingles. What sometimes happens after several years, dirt and sand will accumulate between the layer and flashing, diverting the water and causing a leak. The best way to stop a leak on a skylight is to clean the flashing. The shingles around a skylight tend to trap dirt.
Sometimes the seal between the dome part of the skylight and base is broken. or causing a leak. The best thing is to remove the dome and apply new sealant on the ridge after cleaning and then replace the dome. be sure to make sure it is tight.
Skylights on flat roofs can also have two reasons as to why it could leak.
- The rubber roof could have separated from the metal flashing.
- The dome part has separated from the frame.
The best way is to remove the existing rubber roof material and reinstall a new rubber flashing and making the transition to the flat roof.
The most common reason for skylights leaking is because the rubber membrane has popped loose from the flashing.
In the case of an EPDM rubber roof, it would be very hard to detect the problem. Many times the EPDM rubber itself has deteriorated and cause pinprick holes for water to leak through.
Do not attempt to make repairs on an EPDM roof without the proper materials. You could make it worse.
As in the image with the three skylights, you can see we have prepared the flashing to receive the new rubber roof. Regardless if you install a new roof over the old roof or just making a repair, the procedure is the same.
It is important to get all the old caulking and tar off. You could use Lacquer thinners to clean the metal flashing after you have removed the majority of it.
The flashing has been tarred up over the years. the best is to remove the tar and open the path where water would flow.
Sometimes the skylight will leak between the dome and frame. Apply caulking or a sealant and replace the dome making it tight.
Some Skylights are not meant for flat roofs.
Some skylights were designed to be installed on a pitched roof. Often we will see skylights that are not meant for flat roofs. The following image shows you the type of skylight that should be pitched to an angle. Some skylights are not designed to be on a flat roof. They should be pitched. When you see the frame like this in the image, you know that is for a pitched roof.