QMy basement has flooded twice because of a malfunctioning sump pump. I understand there is an alarm system that signals if there is water on the floor. Do you know of such a product? Where can I get it? -- P. Harrison

AWater-leak alarms are available, and in my experience they work well. These systems have one or more small sensors that are placed on the basement floor, or wherever else a leak might occur, and a battery-operated wall unit that contains the alarm. The sensor is connected to the alarm housing by a fine wire. I used one in a basement for years and found it to be extremely sensitive to water. The alarm's signal, which is much like that of a smoke alarm, could easily be heard on the floor above the basement.

An alarm system of this type can be bought for about $25 from Improvements (www.improvementscatalog.com, item 226775). This alarm has two sensors, and, according to Improvements, is loud enough "to be heard throughout your house." The alarm will sound for up to three days unless it is turned off.

You should also have that sump pump repaired or replaced. Water-leak alarms are definitely worthwhile but no substitute for properly functioning plumbing and appliances.

My 17-year-old house has many nails protruding from the drywall in the walls and ceilings. What is the best way to fix them? How can I prevent more popped nails? -- G. Pak

Drywall nails sometimes pop or protrude because of shrinkage in the wood framing into which the nails are driven. Popping is most prevalent in humid climates where the framing wood is subject to repeated shrinkage and expansion as the humidity changes.

The nails that have already popped can be repaired, but there isn't much you can do to prevent future popping. To make repairs, use drywall screws instead of nails, since screws are much less likely to pop. The screws are best driven with a power drill-driver. The flat, flaring heads of the screws should be driven just below the surface of the drywall, but without breaking the covering. Use drywall screws 11/4 inches long for standard 1/2-inch drywall.

Drive a screw about 11/2 inches below each popped nail, and then extract the nails. Smooth empty nail holes with sandpaper, and use drywall joint compound to cover the screw heads and fill in the holes. Sand the compound smooth when it is dry, then repaint the wall.

My toilet wouldn't flush properly because of mineral deposits in the jets where water enters the bowl from the tank. A chemical was put in the tank to clean the jets. Where can I get more of this chemical? -- N. Simon

I don't recommend putting strong chemicals or cleaners into toilet tanks. The tanks contain rubber and plastic seals that are easily damaged by chemicals, causing leaks and other problems. Mineral deposits can often be removed from bowl jets manually. I use a piece of stiff coat-hanger wire to clean the jets under the bowl's rim and a small knife blade to clean the jet at the rear of the bowl.

Questions and comments should be sent to Gene Austin, 1730 Blue Bell Pike, Blue Bell, Pa. 19422. Send e-mail to doit861@aol.com. Questions cannot be answered personally.