How Prevent or Fix Frozen Pipes

Water damage from bursting pipes is one of the most common homeowners insurance claims, with an average claim cost of about $5,000. Did you know that most pipes that burst are in newly constructed homes that contain mostly plastic pipes? Copper is expensive and most new builds these days use Pex or PVC.

Why Freezing Pipes Burst
Not all freezing pipes burst. Those that do are because water expands when it freezes, adding considerable pressure on the pipes and most often on the relatively weak fixtures at the end of the pipes. It is more common for the ice to form within the pipe and try to expand along the length of the pipe.

Replace Your Valves
Not only should home owners know where the valve is located, they should have it inspected the next time a plumber is on site. If your home has an older gate-style valve, it might be worth the money ($200 to $400) to have it replaced with a more reliable ball valve.

Why Do Pipes Burst?
Water is incompressible, so where water is confined between the expanding ice and a closed fixture, the pressure increases until the pipe ruptures. The rupture will occur at the weakest part of the pipe holding the confined fluid. Therefore, the pipe most likely bursts away from the actual freeze location, and water pressure in a confined volume is a critically important part of the underlying cause.

How Do I Prevent My Pipes from Bursting?
A good way to prevent bursting pipes is to relieve the pressure on both sides of a freeze but opening facets or valves even temporarily. Depending on what your pipes are made of (copper, pvc), that pressure can cause a tiny leak at a joint or crack on a length of pipe, unleashing the full flow of water inside your home.

How Do I Fix Already Frozen Pipes?
The most common way to warm a pipe is to leave it exposed to warm interior air, most often by locating pipes within interior walls—where the temperature on both sides of the wall is usually well above freezing. Using a space heater to warm the room slowly is also a good idea. Alternatively, if a pipe must go in an exterior wall, a builder can locate the pipe so that it lies between the warm room and the wall insulation. In this case, even though the pipe will be cooler than the adjacent room, so long as there is enough insulation to the outside of the pipe to keep it warm, it likely won't freeze.

How to Identify Freezing Pipes
A water line coated in frost (or bulging like a well-fed python) is a good sign that it’s frozen, but not all plumbing pipes are visible. If your faucets won’t flow and your toilets won’t refill following a flush, that’s a good sign your pipes are frozen.

How to Thaw a Frozen Pipe
Before doing anything, shut off the water supply to that section of plumbing (or the entire house if that’s the only option) because the real trouble begins after the thaw. That’s because the frozen water may be acting as a plug, preventing water from spilling out of the cracks in your pipes. When that plug is thawed, water gushes out. It’s a good idea to be ready with a mop, bucket, and towels in case there’s a plumbing leak.

And remember, it’s not the frozen pipes that really get plumbers’ phones ringing, it’s the thawing pipes that leak and spew water after a hard freeze.Use a space heater, heat lamp, or hair dryer to thaw the frozen length of pipe. Wrapping freezing pipes with thermostatically controlled heat tape (from $50 to $200, depending on length) is also an effective way to quickly thaw a trouble spot. Don’t thaw pipes using a propane torch, which presents a fire risk.

What to Do if a Pipe Bursts
If you walk in to discover a swimming pool in your basement, the first thing you should do is shut off the main water supply to minimize flooding. Next, call your plumber. Immediately dry out by removing as much water as possible using mops, sponges, towels, and a wet/dry vacuum. To minimize mold, mildew, and other moisture-related problems, run a dehumidifier in the space until it’s very dry. For big messes, call your insurance agent. The good news is that most homeowners insurance covers burst pipes and the resulting water damage.

Know Where The  Main Water Shut-Off Valve Is
Everybody should know where the main water shut-off is for your house. The sooner you can shut off the water, the less it will cost you down the road.

Which Pipe Materials are Best To Prevent Bursting?
Which type of pipe material is best to prevent freezing? It depends on the specifics of each application and installation. The following are some attributes and drawbacks of some popular pipe materials.

COPPER. Metal pipes and water itself are fairly good conductors of heat. Therefore, a copper pipe that supplies an outdoor faucet might benefit from interior conditions if it extends along the underside of the first-floor framing in an unfinished basement. Some residual heat from the basement will warm the pipe, and the copper will conduct this heat along its length. This may be enough to keep the water in the pipe from freezing. However, because copper is a good conductor, heat traveling along a copper pipe can also be lost rapidly. For a copper pipe that is insulated, if that pipe extends to the outdoors, the insulation may actually prevent heat from reaching the pipe where it may otherwise have been exposed to a relatively warm basement. Further, if there is a gap in the insulation and cold air can blow across the exposed length of pipe, heat can flow rapidly from the warmer parts of the pipe and be lost to the local cooling. Consequently, a pipe may freeze because it is insulated or because its insulation is incomplete.

PLASTIC. It's also important to consider the relative strength and flexibility of the different pipe materials. For example, if a pipe material could simply stretch as the water pressure increased, perhaps a rupture could be avoided entirely. Plastic pipes include rigid (PVC or CPVC) and flexible (PEX), and they don't have the same characteristics as copper when it comes to freezing.

PVC. Polyvinyl chloride pipes (PVC) and post chlorinated polyvinyl chloride (CPVC) pipes are rigid pipes, with thicker walls than copper pipe. These rigid-plastic pipes do not conduct heat very well, so a flaw in the insulated jacket will be less important to a plastic pipe than it would be to copper. PVC and CPVC pipes do possess some ability to expand under elevated pressure, but they may also become brittle at low temperature, and therefore be vulnerable.

PEX. PEX or crosslinked polyethylene is typically more flexible than PVC or CPVC. Further, PEX is generally run in a single continuous line from source to fixture, so there are very few intermediate connections. So long as the fittings are well attached, if the PEX can stretch sufficiently to accommodate an increase in internal pressure, a PEX pipe may freeze and thaw without ever rupturing. However, the overall system vulnerability may still be governed by the components of the system, especially the connections, and even PEX is not immune.

Grizzly Shelter recommends the Protemp Electric Space Heater below for preventing or fixing frozen pipe issues.