Freezing weather can cause big problems for plumbing systems, especially when the water inside your pipes or valves freezes when the weather is very cold. When this happens, it can cause burst pipes, broken valves, and expensive emergency repairs. Luckily, there are some simple steps you can take to help prevent this from happening.
Why do valves freeze?
Valves freeze when temperatures drop below freezing and the water inside the pipes turns into ice. Ice expands as it forms, which puts pressure on the valves and nearby pipes. This can cause cracks or breaks. Outdoor valves, or even those in unheated areas such as cellars, basements, and garages, are most at risk. 8ºF, or -2ºC, is often considered the danger point at which pipes can start to freeze, especially if they are in unheated or poorly insulated areas.
Keep valves warm
One of the best ways to stop valve stock from freezing is to keep the valves warm. You can do this by:
- Wrapping them with foam pipe insulation.
- Using heat tape or heat cables.
- Keeping the surrounding area heated, if possible.
Freezing is especially likely if the pipes or valves are exposed to freezing air or if water seeps inside and doesn’t drain properly. When the valve stem freezes, it can become stuck or break when someone tries to turn it. It is important to properly protect your valve stock from the cold.
How to prevent valves from freezing
- Shut off and drain the outdoor valves
Before winter, shut off the water to outdoor taps and drain them. Disconnect any garden hose pipes. This stops water from sitting in the valve and freezing when the weather gets cold.
- Seal cracks
Cold air can sneak in through cracks near windows, walls, or doors. Sealing these with caulk or weather stripping helps keep warm air in and cold air out.
- Use valve covers
You can buy special covers for outdoor taps and valves. These covers are made from materials that help trap heat and block out the freezing air.
Lagging, thawing and handling a burst pipe
Valves are not the only weak spot in cold weather. When water in a pipe turns to ice, it expands and can split the pipe. The best protection is lagging from a DIY store, fitted carefully so that no bends, fittings or valves are left bare. Keep the temperature in the home steady, and if you go away, leave the heating on low with the thermostat set to at least five degrees. Check that your home insurance covers burst pipes and that you meet its conditions.
If a pipe freezes, warm it gently. Heating it too fast can crack it, so use a hairdryer on its lowest, coolest setting or wrap the pipe in a tea towel soaked in hand-hot water.
If a pipe bursts, turn off the water at the stopcock straight away and call a plumber. Open all the taps to drain the system, and soak up leaking water with towels.