Window won't stop leaking

DEAR BARRY: One of our windows leaked for the third year in a row. We've tried caulking and have even installed an awning over the window: all to no avail. Each time it rains, water drips from the upper edge of the window frame, damaging the paint on the interior sill and bedroom wall. The contractors and handymen we've called can't seem to solve the problem. How can we identify the origin of this leak and get it to stop?

— Gary

DEAR GARY: Sources of window leakage can sometimes be confounding. Everything can look perfect on the outside. Efforts to patch, seal and repair can be made, but the mysterious leaks persist. However, every leak has a cause awaiting discovery, so lets consider three possibilities.

• The most common cause of window leakage is faulty installation, also known as poor workmanship. The perimeter edges of a window must be flashed and sealed in precise ways before the siding, trim or stucco are installed. When shortcuts are taken in these important steps, or when procedural mistakes are made, ongoing leakage can occur without any visible evidence of the actual cause. In cases of this kind, removal of siding or stucco is essential if the repairs are to be effective.

• A less-common cause of window leakage is faulty building design. For example, a second-story deck, without adequate drainage, can allow water to seep into the wall framing, causing leakage at windows or doors below the deck.

• A third possible cause is faulty manufacture of the window unit itself. For example, the weather seals could be improperly made or the sealants could be of substandard quality.

Before proceeding with further attempts to patch and repair, a determination of the actual leak source should be made. Water testing with a garden hose may help to discover the points of water entry. There are also companies that specialize in leak detection by means of infrared cameras. You may be able to locate one of these contractors in your area.

DEAR BARRY: The home I just purchased has a forced-air heating system, and it's the first one I've ever owned. The owner's manual says the filter should be changed regularly, but it doesn't say how often this should be done. What do you recommend?

— Sandy

DEAR SANDY: There is no established time requisite for the scheduling of forced-air filter changes. Filters should be changed when they begin to become dusty, and this can happen sooner or later, depending on a number of variables.

In areas where dust is more prevalent and in homes where forcedair systems are used often, filters may require monthly changes. In relatively dust-free environments or where heating units are used only occasionally, semi-annual changes may be adequate. By checking your filter visually, you can easily determine when a fresh one is needed.

Routine maintenance of your forced-air filter is strongly advised. In addition to filter changes, you can request an annual inspection of the furnace by the gas company to make sure the system is operating safely.