Dripping sound makes new homeowners uneasy

Q: We bought a new house from the builder in April 2004. There is a family bath on the second floor directly above the kitchen. Whenever we open the faucet in the sink in the family bath, we hear a dripping sound (intermittent, crisp "drip, drip, drip" sound) from inside the kitchen wall through which the pipes run. We are worried this could be a leak in a pipe inside the wall.

We have brought it to the attention of the builder several times (we have a warranty), but he insists it is because the pipes are expanding and contracting! But we hear this sound only when we open the faucet upstairs, and we hear it regardless of whether we open the hot-water faucet or the cold-water faucet.

We hired an inspector to do a general inspection at the end of the first year of ownership. He went in the crawlspace but did not report any sign of a leak. What can we do to find what it is and get our peace of mind back?

A: Expanding and contracting plastic drain pipes make more of a tick-tick-tick than a drip-drip-drip sound. So assuming your sound effects are correctly portrayed, at first blush I would have to agree with you that this is not expansion and contraction of the pipes, a very common and irritating phenomenon.

But judging from the word "intermittent," I begin to have doubts. Noise from water in a pipe is predictable and correlated directly to the water running, whereas the creaking from thermal movement can be more erratic.

Thermal creaking can be from hot or cold, although hot water is more the norm. Leaks outside of a pipe make less noise than water actually running inside a pipe, especially if the pipe is not insulated inside the wall (unfortunately, too, many builders fail to insulate around interior plumbing — a way to give a home a feeling of quality and increase owner satisfaction for about 50 bucks. And that is a darn shame).

Plastic pipes actually accentuate noise, which is why old-school cast iron is used in commercial buildings and expensive custom homes, eliminating that tell-tale Archie Bunker toilet sound.

To hopefully ease your mind, leaks will manifest somewhere in the house if the plumbing fixture is used regularly, particularly after two years, either in the wall, the floor, the ceiling or in the crawlspace (or all of the above).

Swelling and staining drywall and visibly wet areas are the clues. If all the previously mentioned areas have been checked for leakage, then worry not about a leak.

Water falling down a vertical pipe that abruptly changes direction (like in a ceiling), water siphoning out of a trap arm due to hair buildup and other dripping noises may unnerve you — and thermal expansion is creepy — but in older homes we call this "character," and people pay good money for that.

Sleep easy, but always be vigilant for leaks, which are caught visually rather than aurally.

Q: My fridge leaks water onto the floor once in awhile, but I have no icemaker, no icemaker connection and no plumbing back there. It is a late 1980s model. The fridge is very heavy, and I can't move it to check. Plus it is filthy behind and beneath, and I don't relish the idea of cleaning out all those dust bunnies. Ideas?

A: Pull off the lower front cover panel. Most likely you will see a pan or tray at or near the bottom rear. This is your condensation drip pan, and it should be removable quite easily, usually by lifting up and pulling up and out like a drawer.

Air from the fan blows over this pan, evaporating the water. Like all bunnies, dust bunnies multiply rapidly under a fridge, and eventually they will get too thick and then air from the fan cannot get to the pan.

Or the pan is not positioned correctly or may be cracked. In any case, the water flows onto the floor. Check the pan, kill some bunnies and clean the coils, too, for more efficient fridge operation.

Darrell Hay is a local home inspector and manages several rental properties. Call 206-464-8514 to record a question, or e-mail dhay@seattletimes.com. Sorry, no personal replies.