Q: Several hot water and steam pipes leading from my boiler are completely exposed and uncovered before they enter the walls. Will painting these pipes with a metallic paint help prevent heat loss or is there any other type of insulation you would suggest?

A: Painting these pipes will help very little, if at all. However, all plumbing supply houses sell a number of different pipe insulating materials you can apply to the outside of these pipes to cut down on heat loss.Some are mastic materials that resemble a dough or putty, and some are wrap-around materials that stick when applied. There are also bulky fiber glass wrappings you can apply. All are simple to install.

Q: My basement is fine during the winter when the heat is on, but in the summer it has a damp smell I cannot get rid of even with the dehumidifier. Should I leave the windows open most of the time?

A: If heat keeps the basement dry and eliminates the musty smell, I think you need either a larger dehumidifier or, better yet, leave the windows open on dry days. More ventilation in warm weather usually solves problems of this kind. An exhaust fan sometimes helps also.

Q: I live in a third-floor apartment in a seven-story building. When water drains from the floors above I get a gurgling sound in my kitchen sink. Not only is the noise annoying, I am afraid the water might back up into my kitchen sink. Is there anything I can do about this?

A: The noise you hear could be caused by a partially clogged drainpipe, but chances are it is caused by a partially clogged vent pipe. Regardless of which it is, this is a job for a plumber to check because the trouble is not necessarily in your apartment; it could be in the pipes above or below you.

Q: We are having a problem with the cold water spigots in our country house. For no apparent reason, when turned on they run cold for about two seconds. Then the water turns warm to hot for about 40 seconds, after which it finally turns cold again. One plumber suggested that maybe the hot and cold water pipes are too close together, but why would this happen after all these years? Do you have any other ideas?

A: It may be that the pipes are almost touching at some point and causing the problem you describe, though why it hasn't happened before I cannot say. It could be that something has shifted, or maybe some alterations or changes were made. You don't say whether the faucet in question is a mixing faucet with a single spout and two separate handles or valves. If it is, it may be that one washer is leaking and allowing the two streams of water to mix. A plumber feeling the pipes under the sink with his hands, and tracing them back if necessary, should be able to locate the source of the trouble.

Q: The top of my dishwater is a butcher block slab held down by two strips of aluminum. On the side next to the sink the wooden slab has absorbed a good bit of water and is somewhat discolored. Is there any way to dry out this slab without taking the whole structure apart?

A: You do not say whether the top has any king of sealer or other finish. If so, this will probably have to be removed first. Once the wood has been stripped clean on top, and then sanded, it should dry quickly enough. I don't know what you mean about "taking the whole structure apart." I assume that you wll have to remove the aluminum strip to do a really good job, and to permit sealing the edges under the metal. After the wood is sanded clean, keep all water away from it until it dries, then apply two coats of a good sealer or oil to the edges as well as to the top before replacing the metal molding around the edge. CAPTION: Illustration, no caption, By Mary Myers for The Washington Post