How to Detect Leaky Skylights

How to Detect Leaky Skylights

Finding the source of most roof leaks is difficult because it begins away from where the leak appears. Water usually comes in from broken, missing, or worn shingles. Water also comes in from poorly sealed or corroded roof flashing around vents.

Detecting Leaky Skylights

The initial step is to pinpoint the cause of the leak by conducting an inspection. If your skylight opens, make sure that it’s completely closed and that the weather seals are in favorable condition. Determine what seasons the leaks usually happen or when there is ice or snow on the roof. Check behind the skylight for leaves, snow, or other debris that could be blocking the flow of water and causing it to back up under the shingles.

Water-Testing for Leaks

If you are unable to locate the cause of the leak by visual inspection or from the attic, wait for the weather to be dry and ask someone you know to help you conduct a water test. In order to do this, one person goes on the roof with a garden hose and the other goes inside the attic with a bucket and flashlight. The person who is in the attic observes while the person on the roof submerges the roof with the hose. The person with the hose begins at the bottom and gradually works uproof until the leak appears in the attic. Once the leak is located, stick a nail through it to mark the location.

Causes of Leaky Skylights

Roof Issues:

A reason why water is leaking could be that the roof surrounding your skylight is not properly sealed. Another issue could be the flashing, which is designed to flow water around the openings.

Poor Installation:

It’s difficult for parts of your home to operate efficiently if the skylights were installed incorrectly. If you suspect that this is the issue, then it’s best to contact a professional to make the proper modifications.

Repairing Leaky Skylights

When leaks happen in an insulated glass frame, it may have allowed water to come in through the window structure and damage the seal. If it’s discovered that the insulating glass is not working properly, then you may re-seal it to prevent more water leakage. You will need to replace the skylight to have condensation removed if the window unit has failed.

To fix a leaky skylight:

  • Lift up the shingles one-by-one and sweep out any debris or dirt.
  • Use a caulking gun that is filled with roofing cement and push it up under the shingle where the flashing coincides with the roofing felt. Push down on the roofing shingles to seal them properly.
  • Seal up any noticeable holes, joints in the flashing, or open seams.
  • Check the seal where the skylight glass intersects with the frame. If you notice any signs of leaking, seal it up with clear silicone caulk.
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