Insights
How to Protect Your Pipes from Bursting This Winter
A burst pipe in the middle of winter is one of the most common and most expensive plumbing problems we get called to. The good news is that most of them are preventable with a bit of preparation before the cold really sets in. Here's how to get your place ready and what to do if something goes wrong.
Water expands when it freezes, and that expansion is what splits pipes. The pipe doesn't always burst while it's frozen either. Often the crack happens, then water gushes out when it thaws and the ice melts. That's why a pipe can seem fine through a frost and then flood the house the next morning. The pipes most at risk are the ones exposed to the cold: outdoor taps, pipes running under the house, anything in an unheated garage or up in the roof space.
The single most useful job is lagging your exposed pipes. Foam pipe insulation is cheap, comes in pre-split lengths, and slips straight over the pipe. Focus on the outdoor and underfloor runs first, since those are the ones that freeze. While you're at it, disconnect and drain any garden hoses before the first hard frost. A connected hose holds water right up at the tap, and when that freezes it can split the tap and the pipe behind it.
Know where your mains shutoff is before you ever need it. It's usually a tap near the boundary or where the supply enters the house. Test that it actually turns, because old valves can seize up. If a pipe does burst, your first move is to shut the water off here, and you don't want to be hunting for it while water pours through the ceiling. If the burst is on a hot pipe, switch the hot water cylinder off too.
If you're going away during winter, don't leave the house stone cold. Setting the heating to tick over on low keeps the indoor pipes above freezing. For longer absences, it can be worth shutting off the mains and draining the system so there's nothing in the pipes to freeze in the first place.
There are a few warning signs worth watching for. If a tap suddenly runs to a trickle on a frosty morning, you may have a frozen section. Don't use a naked flame to thaw it, as that can damage the pipe and is a fire risk. Gentle heat from a hairdryer or a warm cloth is safer, working from the tap end back.
If a pipe has already burst, shut off the mains, mop up what you can to limit the damage, and ring a plumber. The faster the water is off, the less it costs to put right. A bit of foam insulation and knowing where your shutoff is can save you thousands and a very bad day.