HANDYMAN\Finding the mysterious noise in house no humdrum affair.

Byline: Peter Hotton

Well, the saga of the humming sound in the house of P.S. that was driving him bananas is over - maybe.

The intermittent hum in the Newton, Mass. house was low, usually heard only at night and of indeterminate origin. The handyman had one idea that at least made sense: The hum might be coming from an electrical or telephone wire rubbing against the siding or tree branches; the wind vibrated the wire against the house or branch, ergo the hum. The vagaries of the wind is what made the hum intermittent.

Other handy types had different solutions, which they phoned or wrote in, and the handyman is grateful. And if P.S. finds that one of those solutions works, he thanks you, too.

WBZ-TV weatherman Bruce Schwoegler called to suggest that the hum might be from the circulator pump in the hot water heating system. The pump should be oiled, and separated from copper tubing or else the hum will be carried throughout the house.

Yes, but we'd like to know how that copper tubing can be separated from the pump. After all, the pump moves water through that tubing, so the connection is necessary. I suppose a flexible sleeve could be put on the tubing to stop telegraphing of the sound.

Francis Knowlton wrote that his problem was a telephone wire running through a tree. "The wind played the wire against a branch like a bass fiddle, and my bedroom was the sounding board. I cut the branch and the hum was gone."

Jane Bain called to suggest that it might be hot and cold water pipes in contact with each other. Flowing water or the difference in temperature causes the pipes to vibrate. "All I had to do was separate the pipes and the sound ended."

And here's what Walter Donahue had to say about his hum: "It was really more a clicking, but the clicking was so fast that it was like a buzz. Hum, click or buzz, it was coming from my bedroom door and was driving me up the wall, until I realized that the dog slept outside the door, his body right up against it. The latch was just loose enough when the door was closed to vibrate from the dog's heartbeat. God's truth. When I left the door ajar or tightened the latch so it wouldn't rattle in the strike plate, the sound stopped."

Communication: Ain't it grand!

Q: I spilled toilet bowl cleaner on a high-glaze turquoise ceramic tile, and now there's a light spot on the tile. Wouldn't you know, it's right in the middle of the bathroom. How can I get rid of that spot? It's not only light in color, but dull. Can I paint it?

A: That cleaner probably had acid in it, and could have etched the tile, but acids do not usually affect glass, which is what the glaze is. If that did happen, there is no cure. You can try dipping steel wool in paint thinner and rubbing, but I don't think it will help. You could paint that spot or the whole tile as a disguise, and since it is paint on a floor, it will have to be renewed periodically. You can try spot-painting, but if you can't get a perfect match (close but not perfect), do the whole tile. Better yet, replace the tile, if you can get a reasonable match.

Q: I'd like to paint a concrete floor that is already painted, but is peeling. What can I use? The area is 20 square feet around a wood-burning stove. The rest of the floor is carpeted.

A: If the concrete were bare, you could apply a concrete stain: good color, no peeling. But since it already has been painted, you can't do that. Scrape and sand off as much of the paint as you can, then apply a floor paint designed for concrete. A better finish would be an epoxy paint, but it is trickier to apply.

Since this is a small area and around a stove, why not tile it? Again, remove as much paint as possible and apply ceramic tile with a thin-set mortar. The floor will be good-looking, fire resistant, and should last a lifetime.

Q: Should a hot-air furnace be installed in the attic? In my condo under construction, the plan is to put a 100,000-BTU furnace in the basement to serve the very large first floor, and an 80,000-BTU furnace in the attic, serving the smaller second floor. I don't know if the attic is or will be ventilated or not.

A: A thousand times no! No matter how well an attic is ventilated, a furnace should not be there. And no matter how well it and the ducts are insulated, that furnace will make the attic warm, which can cause ice dams in winter. I've had a number of calls from homeowners with just such problems.

There is nothing wrong with a second furnace, and if it cannot be installed on the second floor, then it should be in the basement; you may have long runs of air ducts from basement to second floor, which may reduce the efficiency of the furnace, but with forced hot air and insulated ducts, this can work quite well. Thousands of houses are heated with such long ducts without problems.

Q: I was told that I cannot put asphalt over concrete. Can I put a new concrete driveway over old concrete? A driveway man wants to break up the concrete and cart it away, using new asphalt in its place, for $10,000.

A: It's not a good idea, but concrete over old concrete should be OK; 2 inches will cost less than $10,000; 3 or 4 inches is better. If you do put down new concrete, make sure the old concrete is rough enough to hold the new layer. Breaking up some of the old concrete should accomplish this.

The new layer will be several inches above grade (the ground level), but this can be compensated for by regrading the earth up to the new level. You may have to taper the new layer somewhat where it reaches the garage and/or street level, but this also can work.

Q: I installed a new seat on my toilet; it was the same brand as the toilet, but it rocks from side to side, a disturbing experience. I think the holes are too large for the bolts, because the rocking occurs even if the nuts are tightened.

A: If you can get thicker bolts, that should do the trick, but if the seat bolts are permanently installed, you could not do that. If not, get large nuts that you can screw onto the bolt so they will fill the hole tighter; then use the regular bolt to tighten everything; and install a large washer to make sure the nut doesn't drive itself into the hole. In lieu of the nuts to fill the hole, you could wrap the bolt with duct tape to make it thicker, but this won't work as well as the nuts. The bolt and nuts are plastic, so you could trim the filler nuts if they are too big for the hole.