Chicago Plumbworks is the number for burst pipe repair in Chicago: split and frozen water lines in bungalows, two-flats, greystones, worker cottages and condos. In a Chicago winter a pipe problem shows up as water coming out where it shouldn’t, or as a faucet that gives you a trickle or nothing at all. Water coming out needs the main valve closed right now. A dry faucet needs heat and an open tap before the ice splits the line, and often it’s the same pipe a few hours earlier. When water is pouring and you need someone out for a pipe that can’t wait, close the main first and then call.
How to turn off the water to your house
Short answer
Close the main shutoff, the valve on the water line just inside the foundation wall where the pipe enters from the street, usually right by the meter. Turn a wheel handle to the right as far as it goes, or swing a lever across the pipe. Then open the lowest faucet so the trapped water drains there.
Find the pipe coming in from the street
Go to the basement and look along the foundation wall on the street side for the water line coming through it. The main valve is on that pipe a short way in from the wall, next to the water meter if there is one.
Check for water near power
If you'd have to stand in water to reach the valve or the breaker panel, stay out of the basement and get the power cut first.
Close the valve all the way
Turn a round wheel handle to the right until it won't go further. For a lever handle, a quarter turn closes it. The lever ends up across the pipe.
Drain the lines at the lowest faucet
Open the cold tap on the lowest fixture in the building, often a basement laundry tub, so the water left in the pipes comes out there and not through the split.
Call with the valve closed
Say that the main is off, where the water showed up first, and which faucets were still running before you shut it.
Main shutoff locations in Chicago buildings
Water reaches the building from the City’s main out in the street, so start at the front of the basement and follow the pipe.
| Building | Where to look | Watch for |
|---|---|---|
| Bungalow | Basement, on the front wall, where the line comes through from the street | In a finished basement the valve can end up behind a panel or inside a closet. Find it before you need it. |
| Two-flat or greystone | Basement, toward the front of the building | A single water service means this one valve cuts water to both flats, so let the other unit know first. |
| Worker cottage | Raised basement, on the wall facing the street | These cottages were built before indoor bathrooms. The pipes were added later and don’t always run where you’d expect, so trace the one coming through the wall. |
| Condo or apartment | The building main may be in a room you can’t get into | Look for valves on your own unit’s supply lines, and find out now who has the key to the main. |
| Meter in an outdoor vault | Some meters are in a concrete vault outside | Look inside anyway for a valve where the pipe comes through the foundation wall. |
While you’re at the valve, look at the pipe coming through the wall. If it’s dull gray and soft rather than copper-colored, it may be a lead water line, so mention it on the call.
Pipe burst inside a wall
When a pipe splits inside a wall, the water rarely shows up at the split. It runs down the inside of the cavity and appears wherever it’s stopped, often at the floor or a baseboard, sometimes through the ceiling of the room below or as a dark patch on the plaster a foot or two from the source. By the time you see a stain, the wall has been taking water for a while.
What to do while you wait:
- Close the main, using the steps above.
- If water is reaching an outlet or a light fixture, switch off that circuit at the panel, as long as you can get to the panel without standing in water.
- Move rugs, furniture and anything stored against that wall, and set pans under drips from the ceiling.
- Leave the wall closed. Opening it yourself usually means opening it in the wrong place, since the stain is downhill from the leak.
On the visit, your plumber locates the split and opens the wall right there. The damaged length gets cut out and new pipe joined in, and the rest of that run gets checked before the wall is closed up.
Frozen pipe, no leak yet: what to do
A faucet that gives a trickle or nothing on a bitter morning points to ice in the line that feeds it. Nothing is wet yet, but the ice is already working on the pipe.
Researchers at the University of Illinois found that pipes don’t burst because ice pushes on the pipe wall. Once ice plugs the line completely, more freezing squeezes the water trapped between the plug and the closed faucet, and the pressure climbs until something gives. An open faucet gives that trapped water a way out. Timing is the other half of it. In the same tests, a half-inch pipe in thin foam took about eleven and a half hours to block with ice at 20°F and under five hours at 0°F. On a night below zero, you have hours.
If a faucet has stopped and nothing has split:
- Open the faucet that stopped and leave it open.
- Find the cold section if you can. Check the cabinet under that sink, any stretch along an outside wall, and the spot where the line comes through the foundation.
- Warm that section gently, with no flame anywhere near it, until full pressure comes back.
- Try every other faucet in the building. When one line freezes, others nearby often have too.
- If you can’t find the frozen spot, can’t reach it, or it won’t thaw, close the main and call a plumber for the frozen pipe before it splits.
Why two-flats and porches freeze first
Freezing doesn’t wait for zero. In the University of Illinois field tests, an uninsulated pipe in an unheated space began to freeze once the air outside dropped to about 20°F.
In a greystone or a brick two-flat, the kitchen is at the back of every unit, next to the back stairs, so one flat’s kitchen is right above the other’s. That puts both sets of sink lines in the rear wall, facing the alley and the wind. If a back porch was enclosed and turned into a laundry or a pantry, any pipe running out there is outside the heated house, glass or no glass.
Drafts make it worse. Moving air pulls heat from a pipe much faster than still air, so a gap around a back window, or around the hole where a pipe passes through the wall, can freeze a line in a room that feels fine.
Worker cottages have their own version. They were built without indoor bathrooms, so the bathroom and kitchen plumbing came later. If the bathroom is in an addition at the back of the house, its pipes may have less wall and less heat around them than anything in the original structure.
Finding the second weak spot
When a frozen pipe splits, it splits at the weakest point of a section that took the same pressure from end to end. The University of Illinois work found that the failure can happen anywhere between the ice and the closed faucet. Solder joints and elbows can give way too, and sometimes the break is where almost no ice formed, even inside a heated room.
So the split you can see isn’t the only part of that run that took a beating. The fittings on either side of it, and the faucet at the end, went through the same squeeze and may be weakened without leaking yet. Other lines in the same cold wall may have frozen the same night.
On the visit, ask your plumber to trace the run from the frozen section to the fixture it feeds and check each joint on it. Bringing the water back slowly, before the wall gets closed, shows up a weak fitting while it’s still easy to reach. If another pipe in that wall stopped running during the cold, have it checked on the same visit.
Keeping pipes from freezing next winter
Moving a pipe into heated space is the fix that lasts. The University of Illinois researchers named it the main way to prevent bursts. Everything else on this list slows the cold down.
- Insulate exposed lines. Foam on pipes along outside walls and in unheated spaces slows the ice down. It won’t stop it in a long cold snap.
- Use heat cable carefully. If a line can’t be moved, a good heat cable with a built-in thermostat, installed the way the maker says, keeps it above freezing.
- Shut down the outside faucets. Before the first hard freeze, take the hoses off, close the valve inside that feeds each outdoor faucet, and put an insulating cap over the faucet.
- Stop the drafts. Fix cracked basement windows and seal gaps where pipes pass through outside walls.
- Hold the heat steady. Keep the thermostat at one setting day and night in a cold snap, open sink cabinets on outside walls, and don’t let the house drop below 55°F if you’re away.
If a line froze last winter, it’s likely to freeze again in the same spot unless something about it changes. A plumber can reroute it into the heated part of the building. Where that isn’t practical, a valve that lets the exposed line be drained for the season cuts the risk, and so does proper insulation. Ask about it on a visit before the cold settles in.
Water in the basement, but no split pipe?
If the water is spreading from under the tank, start with a water heater that’s leaking instead. If it’s rising through the floor drain, especially during a storm, the page on water coming up in the basement explains why it happens in Chicago and what keeps it out.