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Finding a Leak

The first step in repairing a leak is finding its point of origin. This can be extremely difficult on a flat roof, so we recommend that you hire an industry professional to find and repair a leak in a flat roof. However, on a pitched roof, do-it-yourselfers can find the leak themselves. You'll still need to hire a contractor to repair the leak, but being able to tell the contractor where the leak is saves time and shows the contractor that he or she is dealing with an informed home owner.

While water testing a pitched roof is not a difficult process, it can be time-consuming and tedious. Be prepared to exercise a bit of patience. The process requires two people, one on the roof and one in the attic (or living space below if no attic exists). You also need the following tools:

  • 1 ladder
  • 1 garden hose
  • 1 flashlight

Then follow these steps:

  • Use the garden hose to run a modest amount of water over the roof at a point below the area where a leak is suspected.

Don't run the hose full blast. Don't use a spray nozzle, and don't force the water between the shingles. Doing so may force water into the home, creating the illusion that you've found a leak when, in fact, you did nothing more than temporarily create one.

Work from the lowest point of the roof (near the eaves or gutters) in an area of about 4 to 6 feet wide. Work your way up the roof a couple of feet at a time. Standing on dry roofing above the water helps prevent a sudden and unexpected slip.

  • Station your partner in the attic and tell him or her to holler at the first sign of water.

The moment your helper sees water, he or she should let you know. A whaling screech will usually do the trick. An inexpensive pair of kids' walkie-talkies allows you to communicate clearly without yelling.