Public Release: 

Faucets That Drip Automatically Could End Burst Pipes In Winter

University of Illinois at Urbana-Champaign

CHAMPAIGN, Ill. - Every home should have some leaky faucets, say University of Illinois researchers who have invented one. Especially homes in the American South.

If Jeff Gordon and Bill Rose had their way, faucets would be designed to drip automatically whenever freezing temperatures threatened to burst water pipes. It1s their easy and cheap solution to an expensive problem. According to estimates from the Insurance Institute for Property Loss Reduction, $4 billion in insurance claims were paid over the past decade for damage from burst pipes.

The leakable faucets solve the problem, which is caused by something other than what most people think, said Gordon - who is on the staff, with Rose, of the U. of I. School of Architecture-Building Research Council. Through research over two years, sponsored by State Farm Fire and Casualty Co., Gordon showed that it1s not ice pushing out on the pipe walls that breaks a pipe.

In fact, 3a pipe usually will burst in a place that has almost no ice in it,2 Gordon said.

The ice ultimately causes the breakage, but it does so indirectly. First, it creates a blockage in the pipe, then ice growth toward the closed faucet dramatically raises the water pressure in that part of the pipe. After a hundredfold increase in pressure - from a normal 40 to 50 pounds per square inch to more than 4,000 - a copper pipe is likely to burst.

3You can make as much ice as you want in the pipe, with no danger it will burst - until a solid blockage occurs,2 Gordon said. 3It1s not the ice itself, but the fact that expansion of the water as it freezes creates tremendous hydrostatic pressure, and it is the water pressure that bursts the pipe.2

So even though measures taken to keep pipes from freezing are important, the ultimate guard against burst pipes is a faucet that leaks when water pressure rises, relieving the pressure well before it reaches the critical point. With such a faucet, Gordon said, 3pipes could freeze, and people could turn on their water and find they had none, but the pipes wouldn1t burst.2

The problem is centered in southern states, particularly along the Gulf Coast, where subfreezing temperatures are rare, Gordon said. Unlike in the north, homes are constructed without attention to placing pipes where they will be protected from utside temperatures.

3They get away with it for years at a time, but then they get a cold snap,2 he said. 3We1re not talking one person lost a pipe - we1re talking about a whole town.2 That scenario becomes a kind of natural disaster.

Gordon and Rose have worked on several designs for their leaky faucets, or 3pressure-relief fixtures,2 and the university is seeking patents on the designs and the overall concept, as well as businesses interested in licensing the technology. In one kind of faucet design, all it takes is a new - but simple - washer. It1s possible their 3$4 billion washer,2 as they jokingly refer to it, could be produced for less than a buck. -cdc-

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