Cook County, Illinois · Chicago
Water spreading, a burst pipe, sewage, mold or smoke? Call to be connected with a restoration company that serves Chicago, Cicero and Schaumburg. Start the steps below while you wait.
Answered 24/7 by a participating local provider. We're a referral service and don't do the work ourselves. How it works
Start here
Pick the closest match. These steps limit the damage and protect your insurance claim. Skip anything that isn't safe.
With 49% of homes built before 1960 and about 40 hard-freeze nights a year, frozen and split pipes are a leading winter risk in the county.
June brings the most downpours to Cook County, part of 6.3 heavy-rain days a year. Check the sump first.
49% of homes here predate 1960, when clay and cast iron sewer laterals were standard. Roots and cracks in those lines are a common cause of backups.
Cook County's wettest day in the 2015–2024 record brought 3.06 inches, and about 80 freeze-thaw days a year mean ice dams in some winters.
2% of occupied homes in Cook County heat mainly with wood or propane, below the Illinois county median of 16.5%.
With 41 muggy nights a year, mold in Cook County can appear within days of a leak. Dry first, then clean.
Local risk profile
Cook County covers 945 square miles of northeast Illinois, with about 5,182,090 residents and 2,276,493 homes. Chicago is the county seat; Cicero, Schaumburg and Evanston are the next largest communities. Half the homes here were built before 1961, half after.
51/100 Water Damage Risk Index: Elevated Cook County ranks 43 of 102 Illinois counties. See the statewide ranking and method.The three factors where Cook County ranks highest compared with other Illinois counties.
Cook County gets more hard-freeze nights than most of Illinois. From 2015–2024 it averaged 40 nights a year at 20°F or colder, the range where pipes in exterior walls, crawl spaces and unheated garages freeze, and 111 nights at or below 32°F. That ranks 32nd of 102 counties.
Cold snaps are the real risk. The worst in the record lasted 18 days below freezing (ending March 2015), and the low bottomed out near -22°F on January 31, 2019.
The freeze season here runs November to March, with January the coldest. If you travel then, leave the thermostat at 55°F or above and open sink cabinets on outside walls.
Freezing nights typically start around Nov 1 and end around Apr 23.
Cook gets fewer downpours than most Illinois counties, but they still fill basements. The county gets about 38.7 inches of rain and melted snow a year, with 6.3 days of an inch or more (95th of 102). Those downpours cluster in June, July and October, when sump pumps and gutters are tested hardest. The wettest day on record brought 3.06 inches on October 15, 2017. The worst three-day stretch dropped 3.86 inches, ending September 30, 2019, the kind of soaking that overwhelms sump pumps and storm sewers.
Freeze-thaw days, below freezing overnight and above it by afternoon, come about 80 times a year here. They're the main driver of ice dams and of water working its way through foundation cracks in late winter.
Housing
Roughly 73% of the county's housing was built before 1980. That puts Cook among the oldest housing stocks of Illinois's 102 counties.
Before 1960 is when 49% of these homes went up. Galvanized supply lines and cast iron drains were standard then, and after 60-plus years both corrode and crack, often out of sight inside a wall or under a slab.
Renters occupy 42% of homes. If you rent, the building is usually the landlord's to repair, but your belongings are only covered by renters insurance.
Beyond water
Cook County averages 41 warm, muggy nights a year (lows of 65°F or more) and gets the most rain in May. Keep indoor humidity under 60%, as the EPA advises, and dry any leak within 24 to 48 hours; in a humid month a wet basement left alone won't dry by itself.
Mold remediation: what to expectMain heating fuel in Cook County's occupied homes: 80% utility gas, 16% electric, 2% propane and under 1% wood. Most homes here heat with gas or electricity, so cooking and electrical faults are the likelier fire sources. Even a contained kitchen fire can send soot through the ductwork to every room.
Fire and smoke cleanup: first stepsCoverage
Calls connect to restoration companies that work across Cook County. The largest communities by population:
Population from ACS 2020-2024 5-year estimates. Townships and unincorporated areas are covered too.
Nearby
Every neighboring county gets more pipe-freeze nights than Cook. All of its neighbors see more heavy-rain days. Its housing is the oldest in the area by share of homes built before 1980.
By the numbers
| Factor | Cook | Illinois median | Rank |
|---|---|---|---|
| Homes built before 1960 | 49% | 38% | 19 of 102 |
| Homes built before 1980 | 73% | 66% | 26 of 102 |
| Homes built 2000 or later | 13% | 15% | 62 of 102 |
| Manufactured or mobile homes | 0.8% | 5.6% | 98 of 102 |
| Vacant homes | 7.7% | 11% | 81 of 102 |
| Wood or propane heat | 1.5% | 17% | 100 of 102 |
| Nights at 20°F or colder | 40/yr | 35/yr | 32 of 102 |
| Days with 1 inch+ of rain | 6.3/yr | 8.4/yr | 95 of 102 |
| Freeze-thaw days | 80/yr | 81/yr | 55 of 102 |
| Muggy nights (65°F+) | 41/yr | 51/yr | 70 of 102 |
Rank 1 is the highest value. Bars run from the lowest to the highest Illinois county; the tick marks the median; orange means higher water damage risk than the median, green means lower.
Questions
Peak risk months in Cook County: freezing from November to March, heavy rain in June, July and October.
Sources: U.S. Census Bureau, ACS 2024 5-year estimates (2020-2024); weather from NOAA nClimGrid-Daily county averages (EpiNOAA), 2015–2024, averaged across the county; county boundaries from Census TIGER. Reviewed 2026-10-21. Methodology