Dear Pat: I have noticed some damp dark spots on my bedroom ceiling after it rains. How do I know whether it is best to have the leaks repaired or to have the entire roof replaced? — Annie H.

Dear Annie: If you are already seeing dark spots on your ceiling don't wait to get your roof repaired or replaced. The dark color is mildew that has developed from the long-term presence of moisture. This moisture could also have already contributed to damage to the structural lumber in the roof and attic.

Although there are several telltale signs that there is a problem with a roof, replacing it or repairing it is not always an obvious decision. The best method is to inspect the roof yourself and then get the opinions of several roofers. Keep in mind, though, that roofers will likely be inclined to suggest replacing the entire roof.

There are many factors that affect the life of a shingle roof. These include the initial quality of the shingles, local climate conditions, proper roof design, proper attic ventilation and general roof maintenance.

Proper roof maintenance includes keeping gutters clean, removing organic matter such as tree branches and leaves, and checking periodically for damaged shingles.

As a rule of thumb, you can expect about a 20-year life from standard roofing shingles. Many warranties on shingles are for 20 years. Some thicker architectural shingles have much longer warranties. If the shingles are less than 10 years old, unless you find many leaks in many different areas, it would be wise to just repair the damaged areas.

If your shingles are in the 10- to 20-year-old range, doing an inspection yourself will help you to make your decision.

First, go inside the attic with a flashlight and inspect the underside of the roof sheathing for signs of moisture. It is often difficult to find the exact location of the leaks because water will often trickle along a rafter for quite a distance before dripping off to the ceiling below.

You may be lucky and see damp spots on the sheathing where the water has come through. Probe these spots with a thin screwdriver to see if the sheathing is still in sound condition. Sheathing often has small pinholes that are not a problem. If you find a pinhole, VERY GENTLY poke a stiff wire into it to see if it easily penetrates the shingles. If it does, there could be a problem.

After checking inside the attic, it is a good idea to get a helper and a good-quality ladder so that together you can safely view the top of the roof.

A typical sign of roofing problems is curled edges on the shingles. This might be caused by age or excessive heat from inadequate attic ventilation. If the curling is extensive and the shingles are brittle to the touch, it will require a tear-off of the old shingles and a new roof.

Inspect the flashings for signs of rust or damage. They are found where the shingles meet the walls or chimney. If the shingles look good, rusted or damaged flashing can be repaired without needing to replace the roof.

Check the valleys where two roof planes come together. This area gets the heaviest water flow during a rain.

Finally, inspect the boots around the base of vent pipes through the roof. They do fail and can easily be replaced without replacing the entire roof.

Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com. To find out more about Pat Logan and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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