CHAMPAIGN — With temperatures headed to dangerously cold levels Monday, it’s time to think about the awful possibility of burst water pipes.
Bill Rose, research architect with the Indoor Climate Research and Training program in the Illinois Sustainable Technology Center, has done interesting research in the area, thanks to a grant from State Farm Insurance.
Rose said most people think that when water turns to ice, it expands the pipe outward and causes the pipe to crack.
"We were able to show through our research that an ice blockage occurs and it grows in length along the pipe. Then, downstream from the blockage toward the fixture, you get elevated water pressure. It’s the high water pressure that causes the pipe to burst, not anything pushing right at the ice,” he explained.
“The ice acts like a piston and causes the fluid pressure to rise and when it gets above the burst strength of the pipe, the pipe will burst,” said Rose.
“Anything that provides pressure relief downstream from the blockage will allow the pipe to turn to ice and back to water without bursting.”
Now that you know the physics behind what could cause an awful problem, here’s the ounce of prevention. And this applies mostly to pipes that are on outside walls or in a crawl space where they may be exposed to cold air blowing in. If your pipes are in a toasty warm basement, you’re safe.
“The old advice is good advice,” said Rose. “Create a drip at the faucet. You need a hot water drip and a cold water drip. The drips can be as small as you want. It doesn’t have to be big. One drip every 10 seconds is enough.”
“Here’s the important thing: If you do that at night before bed and you wake the next morning and the dripping has stopped, that’s okay. Don’t touch the faucet. Just wait for warm weather. A big mistake would be to close the faucet if it’s not dripping.
That’s when it’s most important to keep it in a slightly dripping condition. As the ice grows and pushes, it’s not going to build up pressure because you’ve already provided the relief even though you can’t see the relief. Everything downstream from the blockage will be protected,” he said.
If you don’t believe the research, Rose recommends having a plumber’s name handy.
Also, it’s important to make sure that garden hoses are disconnected from the outside water faucets, especially what he calls the “new style” hose bibbs, or faucets used after about 1960. Otherwise the pressure created by any water that may freeze in the line can cause the faucet to burst.
For the “old style” hose bibbs, those made pre-1960, Rose said it has a shut-off valve outside at the faucet and another inside.
“The ideal way to deal with it is to make sure the one on the inside is closed and the one on the outside is open. That’s the best thing to do for an old style hose bibb,” he said.
Illinois American Water offers these tips if your pipes have frozen:
— Shut off the water immediately. Make sure everyone in the house knows where the shut-off valve is and how to use it. Do not attempt to thaw frozen pipes unless the water is shut off. Freezing can often cause unseen cracks in pipes or joints that will leak when thawed.
— Apply heat to the frozen pipe by warming the air around it, or by applying heat directly to the pipe. You can use a hair dryer, space
heater, or hot water. Be sure not to leave space heaters unattended and avoid the use of kerosene heaters or open flames.
— Once the pipes have thawed, turn the water back on slowly and check for cracks and leaks.
Tips to avoid freezing from Illinois American Water:
- Consider wrapping uninsulated pipes, especially in unheated areas, with electric heating tape, but follow manufacturers' instructions carefully to avoid a fire hazard.
- Seal cracks and holes in outside walls and foundations, especially where cable TV or phone lines enter the house, with caulking to keep cold winds away from pipes.
- If your home is heated by a hot-water radiator, bleed the valves by opening them slightly. Close them when water appears.
- Drain and shut off entirely the water to any unoccupied residence such as a summer or vacation home. A loss of power during a winter storm could cause pipes to freeze. If you intend to leave a property entirely without heat, be sure to drain all water to prevent the
possibility of frozen pipes.
-Set the thermostat at 55 degrees if you're going out of town. Although you may be able to get away with a lower temperature, this setting is considered to be safe for pipes.