A hard freeze is in the forecast: how to keep your pipes from bursting in North Texas

What to do before the temperature drops

To keep pipes from freezing in a North Texas winter storm, wrap exposed pipes outside and in unheated spaces such as the attic, disconnect and drain garden hoses, cover outdoor faucets, and learn how to turn off your main water valve before the freeze arrives. During a hard freeze, let hot and cold water drip slowly from inside faucets and open the cabinet doors under sinks on outside walls. If you will be away, shut off the water at the main valve and drain the outside faucets.

That routine comes almost word for word from the City of Dallas Water Utilities' winter guidance, and it matches what I see after every hard freeze. Homes here are built for summer heat. Pipes run through attics, along exterior walls and up the outside of the house to hose bibbs, and they are not always insulated. A few hours of preparation the day before a storm is the cheapest plumbing work you will ever do.

Why pipes burst, and which ones go first

Water expands when it freezes. The city's guidance puts the result plainly: pipes can burst and cause extensive damage, and flooding from a burst pipe can ruin carpet, furniture and more on top of the plumbing repair. Often the break is not where the ice formed. Pressure builds between the ice and a closed faucet, and the pipe splits at its weakest point, which is why a burst pipe sometimes shows up only after the thaw, when water starts moving again.

In my experience, the pipes that freeze first are the predictable ones: outdoor faucets and the short runs behind them, lines in attics and garages, pipes along exterior walls with little insulation, sprinkler backflow devices standing exposed in the yard, and the crawl space under pier-and-beam homes. If you know where those are in your house, you know where to spend your time.

The day-before checklist

Each of these steps takes minutes. Together they protect the most vulnerable parts of the system. Most come straight from the city's winter preparation guidance.

The sprinkler point deserves a word of its own. The city notes that rain and freeze sensors on automatic sprinkler systems are required by City of Dallas ordinance, because a system that runs during a freeze can coat yards and streets with ice, creating a hazard for drivers and pedestrians and possible liability for the owner. If your controller has no sensor, or you are not sure it works, switch the system off before the cold arrives.

• Wrap exposed pipes outside and in unheated areas, including the attic
• Drain and remove garden hoses from outside faucets
• Cover outdoor faucets with hard foam covers or wrap them with cloth
• On a pier-and-beam house, cover the vents around the foundation
• Turn off the irrigation system if it lacks a working freeze sensor, and protect an exposed backflow device
• Find your private shutoff valve and make sure you can turn it
• Keep the garage door closed if water lines or a water heater are in the garage

Finding the shutoff valve before you need it

If a pipe bursts, the only thing that matters is how fast you stop the water. The city notes that the private shutoff valve is often near an outside faucet close to the house. Homes with in-ground irrigation may have it near the irrigation valves, often near the property line. Older homes may have a buried valve with a small L-shaped iron handle; turning it perpendicular to the pipe stops the flow to the house.

Find yours this week, not during the storm. Make sure it turns, keep the tool you need next to it, and show everyone in the house where it is. If it is stuck or will not close fully, have it replaced before winter. A smart shutoff valve, which closes the main supply automatically when it senses a leak, is worth considering for a house that sits empty for days at a time. For a water emergency where you need help turning the water off or on at the meter, the city says to call 3-1-1.

While the freeze is on

During a hard freeze, the city recommends letting hot and cold water drip slowly from inside faucets and opening cabinet doors under sinks on outside walls. Moving water is harder to freeze, and the open doors let warm room air reach pipes inside the wall cavity. Keep the heat on, even if you lower it overnight, and do not shut off heat to rooms you are not using.

If you are leaving home for several days, the city's advice is to turn off the water at the private shutoff valve and drain all outside faucets. If water stays in the pipes and a freeze hits while you are gone, you may come home to a flooded house. Opening a faucet or two inside after the main is closed helps drain what is left in the lines.

The things people forget until they break

The water heater is one. If it sits in a garage or an attic, it and the pipes connected to it are exposed to the cold. Keep the garage closed, make sure the pipes at the heater are insulated, and if you lose power for a long stretch, keep an eye on the lines around it. If a pipe near the heater bursts, turn off the heater along with the water so it does not run empty.

The irrigation backflow device is another. It usually stands above ground in the yard, full of water, with nothing to protect it. Wrapping it and shutting off the irrigation supply, if your system has a separate valve, saves a repair that often goes unnoticed until spring.

The third is the hose left connected to an outdoor faucet. It traps water in the faucet body and the pipe behind it, which is exactly where the freeze does its damage. Disconnecting every hose is the single easiest step on this page, and it is the one most often skipped.

If a pipe freezes anyway

The first sign is usually a faucet that gives a trickle or nothing at all when it should run. Leave that faucet open so water has somewhere to go as the ice melts. Then look for the frozen section, usually along an exterior wall, in a cabinet, in the attic or where the line enters the house.

Thaw it gently. A hair dryer, a heating pad or warm towels applied to the pipe, working from the faucet back toward the frozen spot, is the safe way. Never use an open flame, a torch or a propane heater on a pipe or inside a wall. Check for cracks and drips as the water returns. If you cannot find or reach the frozen section, or the pipe is inside a wall, call a plumber rather than opening the wall yourself.

If a pipe has split and water is spraying or pouring, close the main shutoff immediately, turn off the water heater, and call. We answer 24 hours a day and do not charge more for nights, weekends or holidays, which matters when a freeze hits on a weekend.

Once the ice is gone: check for hidden damage

Some freeze damage is obvious. Some shows up days later as a ceiling stain, a damp wall or a water bill that jumps. After a hard freeze, walk the house, look at ceilings under the attic, check under sinks and at the water heater, and look at outdoor faucets and the irrigation backflow device. Then do a meter test: with every fixture off, watch the water meter or its leak indicator. If it moves, water is escaping somewhere. My guide on the signs of a slab leak explains the full test.

If water has already reached floors or walls, stopping the leak is only the first step. This restoration guide on the first 48 hours after finding standing water covers drying and documentation. Take photos before cleanup, keep every invoice, and call your insurance agent early; whether damage is covered depends on your policy, and an agent such as Aaron Husman can explain what yours says.

Upgrades that make the next freeze a non-event

If the last storm caught you, a few changes make a real difference. Frost-proof outdoor faucets place the shutoff inside the warm wall instead of at the exposed spigot. Insulation on attic and exterior-wall pipe, done properly, protects the most exposed runs. Lines that keep freezing can sometimes be rerouted away from cold spaces, and when a house has had several freeze breaks in old pipe, a repipe with modern material may be the better long-term answer; my guide on what happens during a whole-house repipe explains that process.

A working shutoff at every fixture, a main valve you can actually turn, and a smart shutoff valve round out the list. None of these are expensive compared with a single burst pipe in an attic.

Getting your house ready with us

Fall is the best time to look at freeze protection, before the forecast forces the question. When you call us, the technician can locate and test your main shutoff, check the outdoor faucets and exposed lines, and recommend the changes that matter for your house, with a job price for each before any work begins. Our Home Guard membership includes a yearly plumbing safety check, and my once-a-year plumbing checkup lists what to look at on your own.

When a freeze does cause damage, we are available around the clock across Dallas, the Park Cities and the northern suburbs. We call ahead to confirm the arrival time, explain the repair options, and our work is guaranteed.

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