How to Keep Pipes From Freezing in a Chicago Winter

The kitchen sink in a lot of Chicago two-flats sits against an exterior wall that’s been taking January head-on since the Coolidge years. Figuring out how to keep pipes from freezing in a house like that starts in November, well before the forecast shows a number below zero. A frozen pipe costs you an evening without water. A burst pipe costs a wall and the ceiling under it. So we split the work into November jobs and cold-night jobs, with thawing last.

Which Pipes Freeze First in a Chicago Home

CMAP’s June 2026 snapshot puts 38.8% of Chicago housing before 1940 and another 28.7% between 1940 and 1969. Two homes in three run on plumbing older than the moon landing. Frozen pipes in those homes show up in the same spots every winter. Knowing how to keep pipes from freezing starts with that map, and the Red Cross guide to frozen pipes reads like a tour of a Chicago basement.

• The unheated basement of a two-flat.
• An enclosed back porch with the washer on it.
• Any sink cabinet on an exterior wall.
• Garage lines, if the water runs out there.
• The hose bib out back.

The Red Cross adds attics and the crawl space under a bungalow addition. A greystone built in 1905 had its pipes routed by someone who’d never heard of pipe insulation. The coldest stretch is where the service line comes through the foundation near the rim joist.

Before the First Hard Freeze: 6 Jobs for November

The cheap part of how to prevent frozen pipes happens on a mild Saturday, while the hardware store’s still got foam.

1. Hoses off the spigot and drained.
2. Close the hose bib valve indoors.
3. Foam on every exposed basement pipe.
4. Heat cable only if it’s UL-listed.
5. Gaps around wall pipes get sealed.
6. A boiler tune-up before December.

How to keep pipes from freezing at the hose bib takes one valve, so once the interior shut-off valve’s closed, open the outdoor faucet so the water left in it can drain the line and expand without splitting anything. The IBHS winter checklist says homes built before 2010 rarely have a frost-proof sillcock, which describes almost every bungalow on the Northwest Side. Heat tape for pipes goes on garage and porch runs where a foam pipe sleeve isn’t enough. A fiberglass wrap handles the awkward bends. While you’re down there, find the main shut-off valve by the water meter and turn it once. A valve that hasn’t moved since 1987 picks the worst night to stick.

During a Cold Snap: Drip, Open, Hold the Heat

An Extreme Cold Warning on the phone, the kind our Chicago weather alerts page explains, is the signal for the night shift. How to keep pipes from freezing on a polar vortex night comes down to warm air and moving water. The Red Cross wants a thin drip of cold water from any faucet fed by exposed pipes.

Kitchen and bathroom cabinet doors stay open so the room’s heat can reach the sink cabinet. The bleach under there moves to a shelf the kids can’t reach. The thermostat stays on one setting day and night, and the Red Cross admits that’ll nudge the bill up. The garage door stays shut if a line runs through it. If you’re leaving town for the holidays, it’s 55°F or higher on the thermostat and a neighbour with your key.

Rather hand this one off? Get a written quote

Renting or in a Condo: What You Control

Heat in a building with a shared boiler is the owner’s job under the Chicago heat ordinance. Your apartment’s got to hold 68°F between 8:30am and 10:30pm from September 15 to June 1, then 66°F overnight. A cold unit gets a written note to the landlord or the management company, and a complaint to 311 if nothing changes.

Your own part’s small and still useful. Open the cabinet doors and keep a faucet on a trickle. Tell the landlord about the icy wall behind the sink before it turns into a story. The boiler and the shared risers aren’t yours to touch. Who pays for a split pipe’s written in the lease or the condo association documents.

Signs a Pipe Is Already Frozen

The Red Cross says a faucet that gives a trickle, or nothing, points to an ice blockage. One fixture going dry while the bathroom sink still runs narrows it down to the pipe feeding that spot. Frost on an exposed copper or galvanized line in the basement is about as subtle as a billboard.

What to do if pipes freeze depends on how much of the house went dry. With every faucet dead, text the neighbour upstairs first. Dry taps across the block mean a city main or a frozen service line, which makes it a 311 call. Dry taps in your place alone mean the problem’s yours, somewhere between the water meter and the first faucet.

How to Thaw Frozen Pipes Safely

Thawing is what happens when how to keep pipes from freezing didn’t work out, and the Red Cross version of how to thaw frozen pipes starts with the faucet open. After that, how to unfreeze pipes in a Chicago basement is mostly patience and the hair dryer from the bathroom.

1. Open the faucet on that line.
2. Heat goes on near the faucet first.
3. A heating pad or hot towels work.
4. Keep at it until full water pressure returns.
5. Every other faucet gets checked after.

A space heater’s fine if it stays well away from boxes and laundry. The Red Cross rules out a blowtorch along with kerosene or propane heaters and any open flame. A freeze inside the wall, or one you can’t find, goes to a plumber. If the pipe has already split, close the main shut-off valve first and call our frozen pipe repair in Chicago team.

What a Frozen Pipe Costs in Illinois

State Farm took more than 20,000 frozen pipe claims between January 2024 and June 2025 and paid out over $628 million. Illinois came first on its list of states. The average check was above $30,000, which buys a kitchen remodel nobody picked.

NWS normals for 1991 to 2020 put the average Chicago January at 25.2°F. The NWS Chicago record cold of 2019 took O’Hare to -23°F on January 30, the coldest in 34 years, with a wind chill of -52°F. A few feet of foam sleeve is how to keep pipes from freezing on a budget, and it looks like a bargain next to either number.

When to Call a Plumber

Plumbing frozen pipes turns into our job once the hard part’s out of reach and how to keep pipes from freezing is last week’s problem.

• The frozen section’s inside a wall.
• An hour of heat changed nothing.
• A thawed pipe now drips or shows a crack.
• Every faucet in the house is dry.

A drip after thawing’s a job for our leaking pipe repair crew, and a cracked hose bib or kitchen tap goes to faucet repair. Frozen pipe repair Chicago calls are priced by the job, and the emergency fee’s only there when you need us tonight.