Preventing frozen water pipes
In December 1983, an unusually severe freeze settled over the United States from northern Minnesota clear through Louisiana. When it was over, the insurance industry began counting the cost in burst pipes and water damage: It totalled some $840 million nationwide. David Hurst recalls that his State Farm Insurance company, based in Bloomington, Ill., had to pay out $140 million in claims. Since that time, Mr. Hurst has monitored the frozen pipe problem, and concluded that a few simple precautions would prevent much of the recurring damage. These are relatively inexpensive precautions that a majority of homeowners could undertake themselves.
``A burst water pipe might not be the worst tragedy you can face,'' Hurst says, ``but it sure can cause a lot of inconvenience and some loss of money - even if you are insured.'' Most homeowners, he points out, carry a deductible of $250. In other words, the insured pays the first $250 of the average $2,000 frozen-pipe claim.
Along with insulation, wraparound electric heating tapes are particularly useful in preventing freezing pipes, Hurst says. Whenever the temperature of the pipe drops to near 45 degrees F., the heating tape warms up and maintains the pipe at just above freezing temperatures. Because only low heat is required and because the tape warms only the pipe and not the room, the tapes are a most energy-efficient way of avoiding frozen pipes.
Here are the basic precautions homeowners might take to avoid the problem of freezing pipes:
Put adequate insulation around pipes that are vulnerable to cold air intrusion. There are several types, ranging from fiberglass to foam, available on the market.
Wrap heating tapes (approved by Underwriters Laboratories Inc. or similar organizations) around pipes where insulation alone is not be adequate. Instructions suggest adding insulation over the tape, as long as the insulation does not include vinyl foam. A fiberglass insulation is deemed best. Heating tapes come in two kinds: the kind where the tape or cable must not cross, and the other where crossing is acceptable. Most currently retail in the region of $1.25 a foot.
If possible, use an indoor valve to shut off the water supply to outdoor faucets. Open spigots to drain water from the outdoor faucets.
If you have pipes in an outside wall near a sink, leave the cabinet doors beneath the sink ajar so warm air can get in.
If you cannot insulate or otherwise protect some vulnerable pipes, keep the water trickling from the faucet farthest from where the water supply enters the house. This will keep water moving through most of the plumbing and discourage freezing.
An alternate plan, if you're leaving for some time, is to shut off the water and drain the water supply by opening a faucet at the lowest point in the house. Put antifreeze in the toilet bowls and in the traps under the sink and tub (and any other place where water cannot easily be drained away). But be sure to keep it out of pipes that carry drinking water.
If, despite all these precautions, you still get a frozen pipe, don't try to thaw the pipe with an open flame. Call a plumber instead.