Uninsulated pipes installed in unconditioned crawl spaces or attics can freeze when the outside ambient temperature falls to 20F or below.
I am a little late in the season for this one, but here in the Southwest part of the country, winterizing our plumbing is perceived as not a big deal, but in reality, we have more frozen pipes in our part of the country than Northern climates. Our building code are more lenient and allow methods that would never be considered in Michigan or Wisconsin. Several years ago, Southern Louisiana had extreme cold weather over the Christmas holidays. The amount of broken water pipes almost called out the National Guard, due to the extreme loss of water pressure in the city water supply. If you live in Baton Rouge or Houston, it would not be uncommon to find your main water pipe exposed on the outside wall of the house before it goes in the house. For that reason, these tips may apply to homeowners that live in zones 8A or greater as defined by the USADA Hardiness Zone Map.
According to the Building Research Council at the University of Illinois, uninsulated pipes installed in unconditioned crawl spaces or attics can freeze when the outside ambient temperature falls to 20F or below. However, high winds or “wind chill “can augment this number potentially causing frozen pipes at higher temperatures. Wind chill typically impacts pipes that may be exposed to insulation leaks in the building envelope. For example, a water pipe in an exterior wall without insulation is at risk, add the fact that a crack in the exterior wall near the pipe will allow colder temperatures to increase the opportunity for a frozen pipe.
Key Inspection Points and Action Items:
- Wrap exposed pipes: Especially outside pipes, but don’t forget pipes under the house in crawl spaces as well as in the attic. All Home Centers sell foam sleeves to cover the pipes. This is cheap insurance as these sleeve are about $2.00 per 8 feet.
- Cover or wrap the exterior faucets. Home Centers have a solution for faucets that protrude from the wall, but you will have to be creative for faucets that surface out of the ground. My grandmother always tied an old hand towel around the outside faucets…. its pretty ugly but it worked.
- Caulk the cracks: Check the exterior of the house, especially in relation to faucets or pipes on exterior walls. Ensure the surface is well sealed as not to allow cold air to seep into the wall cavity.
- Open cabinet doors: In extreme conditions or extended vacations, open cabinet doors associated with all kitchen and bathroom faucets.
- Dripping Faucets: If it appears you may experience sub 20 degree weather, and you have pipes (especially on the North side) that are at risk, let the hot and cold water run. Granted, this breaks my rule of wasting water, but if possible, try to capture the water in a pan or pail and water your house plants. They are probably drying out since your are running your heater anyway. TIP: If the open faucets stops dripping, leave it open as this will allow the ice formation to expand without damaging the pipes.
- Turn off and drain Lawn Sprinkler System: If cold weather conditions are forecasted for several days, you may consider turning off and draining your sprinkler system. Hopefully you have a cut off and drain. For some of us, watering in the winter is still necessary due to the lack of rain or snow, so you may just turn it off based on the weather forcast. TIP: If you do not have a drain at the sprinkler cut-off, you can activate the sprinkler system for a few seconds to remove presure from the lines.
- Disconnect and drain exterior water hoses: A water hose connected to an exterior faucet will telegraph a frozen condition into the faucet potentially causing the faucet to freeze.
- Extended vacation:If you are leaving the house for several months, you may consider turning the water off and draining the pipes. As an alternative to that, leaving your Central Heater on 60F, will alleviate this situation. Look for future posts on “Extended Winter Vacations” for more details.