Basement Waterproofing Rules in Illinois: What Chicago, IL Homeowners Should Know
Before anyone cuts into a basement floor in Chicago, Illinois, a handful of rules decide who may do the work, what the paperwork has to say and where sewer water gets reported. This page sets them out in everyday language, with the offices that can confirm each one. This is a summary of public law, not legal advice.
Rules at a Glance
Short on time? These five points cover most of it.
- No state waterproofing license. Inside Chicago, most building work needs a City-licensed general contractor; suburbs keep their own lists.
- Plumbers and drainlayers stand apart. Sump hookups to the drain system, backwater valves and overhead sewers take a licensed plumber; sewer lines take a licensed drainlayer.
- Jobs over $1,000 go on paper. Illinois requires a written contract and a consumer-rights pamphlet before you sign.
- Some deals can be undone. A contract signed at home can generally be canceled within 3 business days, or 15 for buyers 65 and older.
- Floor drain water is a sewer question. In Chicago, report it to 311.
Checking a Contractor's License
Illinois has no statewide license for basement waterproofing, though the state and the City both license plumbers. Inside Chicago, the Department of Buildings says most construction, alteration and repair work needs a City-licensed general contractor that carries insurance.
To check a name, search the Department of Buildings' licensed-contractor lookup on chicago.gov, which also shows when the license and its insurance expire, or call 312.744.3449. The business on your estimate should match the record exactly.
In Chicago, plumbing runs through a City-licensed plumbing contractor, and private sewer work needs a licensed drainlayer holding a City sewer permit.
The City's code treats anyone who submits a bid, offers to take on building work or claims to be able to do it as a general contractor. Chicago IL Basement Waterproofing does none of those things and holds no City of Chicago contractor license. It hands your request to a single independent local contractor, and that contractor comes out, prices the job in writing and carries out whatever you approve. Advertising space here is open to contractors, free during a trial for now; homeowners are never charged and never given anything.
Before You Sign Anything
The Illinois Home Repair and Remodeling Act (815 ILCS 513) reaches basements and sewers along with most other repairs to a home. On a job over $1,000, the contractor owes you a written contract or work order stating the total cost and its business name and address. Before you sign, it must also give you the pamphlet "Home Repair: Know Your Consumer Rights" and have you sign that you received it.
Tie each payment to a finished stage of the work, never the full price on day one, and make sure the contract covers these details.
- The drain route. Which walls the drain follows and how many feet in total.
- The pump and the outlet. The pump model and where the discharge water ends up.
- Permits and trades. Who pulls each permit, and which licensed plumber or drainlayer does any plumbing or sewer work.
- Warranty terms. What it covers and whether it moves to the next owner.
- Proof behind the name. Liability and workers' comp certificates, a local address and references.
- Red flags. Cash-only terms, full payment up front or pressure to sign today.
How to Cancel in Writing
Illinois offers two windows for changing your mind, and both generally depend on the deal being made at your home. Under the home-sales section of the Consumer Fraud Act (815 ILCS 505/2B), a buyer can generally cancel by notifying the seller within 3 full business days.
Buyers 65 or older get longer. Under 815 ILCS 513/22, a home repair contract signed at the buyer's home can generally be canceled within 15 full business days after the day it was signed.
Either way, cancel on paper: date it, add your name and address and a plain line saying you are canceling, keep a copy, and send it with proof of delivery. If a dispute won't settle, the Illinois Attorney General's Consumer Protection Division takes complaints, as does the city or village that licensed the contractor.
Local Programs Worth Knowing
Most of the city and many inner suburbs use combined sewers, where rain runoff and household wastewater share pipes, so a heavy storm can push that mix back up through floor drains. After the July 2, 2023 storm, Chicago logged more than 12,000 water-in-basement reports to 311 in two weeks (WBEZ).
Report basement water inside Chicago to 311 (312.744.5000 from outside the city), saying whether it's clean or dirty and where it came in. The Department of Water Management (312.744.6635) handles the public sewer but doesn't work on private property, and the lateral running from your house to the street sewer is yours to maintain.
The Metropolitan Water Reclamation District (MWRD) runs the regional system behind those sewers. It suggests a check valve or an overhead sewer, plus disconnected downspouts, and in 2026 put a backflow device at roughly $10,000 per household. Chicago has no citywide program that helps pay for one.
Some suburbs do. Oak Park, IL offers a Sewer Backup Protection Grant covering half the cost, up to $3,500, of an overhead sewer or backflow-valve system for owner-occupied homes of one to four units. It needs a proposal from an Illinois-licensed plumbing contractor, village permits and disconnected downspouts, first come, first served; check the village's current terms with Housing Programs at 708.358.5410.
Standard homeowners policies often leave out sewer backups unless a separate rider was added, and seepage is commonly excluded. Read your policy and ask your insurer or agent; this site has no role in insurance.
Who Issues Permits
Chicago permits come from the Department of Buildings at 121 N. LaSalle Street. Sewer work needs a City sewer permit obtained by a licensed drainlayer, plumbing needs a licensed plumbing contractor and a permit, and most building work needs one too. Whether drain tile, a sump or an overhead conversion alone needs a permit depends on the job, so the contractor confirms permits with the Chicago Department of Buildings.
- Oak Park, IL. Drain tile and sump permits: Permits, 123 Madison Street, 708.358.5430. Contractors register with proof of insurance.
- Evanston, IL. Contractors working under a permit register with the City: 311 or (847) 448-4311, 909 Davis Street.
- Park Ridge, IL. Contractors register yearly. Community Preservation & Development, 505 Butler Place, 847-318-5291.
- Oak Lawn, IL. A yearly village license; plumbers file a Chicago or Illinois plumbing license. Permits: 9446 S. Raymond Avenue, (708) 499-7800.
- Orland Park, IL. Contractors must be licensed with the village before any permit. Village Hall: (708) 403-6100.
Chicago's 311 serves the city alone; suburbs take sewer backup questions through their own public works departments.
Rules Questions, Answered
Does Illinois license basement waterproofing contractors?
Not as a separate trade. Illinois licenses plumbers, and Chicago licenses general contractors for most building and repair work in the city; confirm a name through the Department of Buildings' lookup or at 312.744.3449. In a suburb, the village or city runs its own registration or license, so its building office has the answer.
What must a contractor give me before I sign?
On any job over $1,000, Illinois requires a written contract or work order showing the total cost and the contractor's business name and address, plus the pamphlet "Home Repair: Know Your Consumer Rights" before you sign. If either is missing, hold off until it arrives.
Who do I contact when water comes up a floor drain?
Water rising through a floor drain usually means a sewer backup, not seepage. Inside Chicago, report it to 311 with whether the water is clean or dirty. In a suburb, contact your own public works department. A check valve or overhead sewer, put in by a licensed plumber, is what MWRD suggests against repeats.
Sources
All read 2026-10-10; check the current version before relying on one.
- Chicago Municipal Code ch. 4-36. General contractor licensing.
- 815 ILCS 513. The Home Repair and Remodeling Act.
- 815 ILCS 505/2B. The 3-business-day home-sales cancel right.
- 225 ILCS 320. The Illinois Plumbing License Law.
- chicago.gov Buildings and Water Management pages. License lookup, sewer permits, water in basements.
- mwrd.org. Combined sewers, laterals, check valves and overhead sewers.
Ask About Your Job
With the rules sorted, the next move is a written number for your own basement. Send the short request form, and one independent contractor from the Chicago area will get in touch, see the space and put scope and price in writing. Want a ballpark first? The cost calculator gives a rough range, and the wet basement checker helps sort out where the water may be coming from.