What to ask before you sign, and the red flags

Two things this page is not. It is not a screening service: we do not screen contractors, and every check below is one you run yourself on a public government system. And it is not a ranking, because we cannot document one, so no contractor is named or scored anywhere on this site. The pillar this page sits under is choosing a Chicago window contractor.

The 12 questions, and what a real answer sounds like

The point is not to interrogate anyone. It is that the answers to these 12 questions are the only things that make two quotes comparable, and a firm that answers them cleanly has told you something real about how it runs a job.

Scope and product: the five that decide the price

Ask this	A real answer sounds like	Why it matters
Is every unit the same type, size and shape as what it replaces?	A yes, or a specific list of which units change and why	Chicago defines in-kind replacement as "of the same type, size, and shape". That one word decides your permit answer
What frame material, named specifically?	"Vinyl", "fiberglass", "aluminum-clad wood", with the line and series	"Premium" and "builder grade" are not materials. Pricing splits hard by material, which is what the material cost page compares
What is the glass package, and its U-factor?	A number, in writing, per unit type	U-factor is the number that matters in a Chicago winter, and it is the one spec a cheaper bid quietly drops. See glass and U-factor
Does each replacement keep at least the same glass area and the same openable area?	Yes, with the unit sizes shown	Chicago's own permit terms require a replacement to have "an equal or greater area of transparent or translucent glazing", and in a residential building it "may not have less openable area than the widows it replaces" (the typo is the city's). A frame-in-frame insert can shrink both
What happens to the interior and exterior trim, and the wrap?	A described finish, in the written scope	This is the line most often missing from the cheaper bid, and the one most often argued about afterwards

In-kind definition and the glazing, openable area and opening control device terms read at chicago.gov, 2026-08-11.

Paperwork: the three that catch the most

Ask this	A real answer sounds like	Why it matters
Which specific part of my job requires a building permit?	A named condition: a resized opening, a changed operating style, a building over four stories, landmark status	If nothing in the scope triggers one, the city's list says no building permit is required. See the section below
Is my property a landmark, or in a landmark district, and who is checking?	"We will confirm with the Historic Preservation Division before ordering"	Chicago says the exemptions "may not apply" on designated or proposed landmark property, and does not say which survive. Detail on the landmark page
My house predates 1978. How are you handling lead?	A firm certification number for renovation, repair and painting work, plus an answer on the city filing	EPA requires "anyone paid to perform work that disturbs painted surfaces in homes, childcare facilities and preschools built before 1978" to be certified in lead-safe work practices. EPA does not specifically name window replacement, but window work commonly disturbs paint, so ask. Chicago's permit terms separately state work "must comply with lead-safe work practices required by city, state, and federal laws", and that you "may be required to file a separate Lead-based Paint Renovation, Repair, and Painting Form" with the Chicago Department of Public Health

US EPA, Renovation, Repair and Painting Program, read 2026-08-12. Exemption lists, landmark caveat and permit terms read at chicago.gov, 2026-08-11. Firm certification is searchable at the EPA lead firm search, confirmed reachable 2026-08-11.

The business behind the crew: the four you check yourself

Ask this	A real answer sounds like	Why it matters
What exact business name goes on the contract, and what is its City of Chicago General Contractor License number?	A business name and a number beginning TGC	The license is held by the business, not the person at your table. Search the business name on the city's lookup and confirm the entity you checked is the entity you sign with
When does the insurance on file expire?	A date that comfortably clears your install date	The city states that "A general contractor license is automatically inactivated if the associated insurance policy expires". The lookup shows this date, and most people skip it
Will the insurer or its agency send me the certificate directly?	Yes, with limits and completed operations shown	The lookup proves a policy was on file and when it lapses. Only the certificate names the coverage. "Completed operations" is the part that responds after the crew leaves
Who is physically on site, and are they your employees or a subcontractor?	Either answer, stated plainly	Both are normal. The city exempts "subcontractors and employees working under a licensed general contractor" from holding the license personally. What matters is which entity your contract is with

City of Chicago Department of Buildings General Contractor License page, and the Licensed Trade Contractors lookup, both read 2026-08-11. Field names read from a live returned record.

The permit line item, in detail

This is the single question on the page most likely to change what you pay, and it is worth knowing the rule before the sales visit rather than after it.

Chicago publishes a list of work that does not require a building permit. In a residential building up to four stories above grade, it includes "Repairing or replacing (in-kind) an exterior window or skylight in the existing opening". In any building, taller ones included, the list also covers repairing a window, replacing the glass in an existing sash, fitting a storm window or an insect screen, and replacing a ground-level window in kind where no part of the exterior wall is cut away. In-kind is defined by the city as replacement using new elements "of the same type, size, and shape".

Chicago's housing stock sits mostly inside that second list. A bungalow, a greystone, a two-flat, a three-flat and a coach house are all residential buildings up to four stories above grade. So on a straight in-kind swap in a house like that, on a property with no landmark status, the city's own published list says no building permit is required. A permit line on that quote is not automatically dishonest, and it is not automatically legitimate either. It is a question.

Both exemption lists and the in-kind definition read at chicago.gov, 2026-08-11.

Three ways a permit line can be honest

• The scope actually triggers a permit. A resized opening, a new opening, a different operating style, a building over four stories, or a unit above ground level in a non-residential building all take you off the exemption list.
• The job needs the express route and a licensed contractor to file it. On the Express Permit Program window worktype the city requires a licensed general contractor on every application, with the class (A to E) set by project cost, plus at least one existing condition photograph and an energy and water efficiency compliance form. A condominium property also needs a condominium association approval letter. That is not a form a homeowner files alone.
• Landmark status is in play. The city says the exemptions "may not apply" on designated or proposed landmark property and does not enumerate which ones survive. Confirming that is real work with a real reviewer attached.

Three ways it can be a line item for nothing

• Nobody can name what triggers it. "The city always requires one" is not an answer, and on an in-kind residential swap it contradicts the city's own list.
• The line does not change when the scope changes. If you drop the one casement that would have made the job not in-kind and the permit line stays the same, ask what it is attached to.
• It carries a fee amount nobody will trace. Ask which city fee the line corresponds to and what the rest of it covers. No permit fee figure appears anywhere on this site, because Chicago publishes no window-permit amount that was readable at the source on 2026-08-11, and we do not repeat a number we cannot trace to the agency that charges it. Ask the Department of Buildings for the current fee for your worktype.

One thing "no permit required" never means is "no rules apply". Chicago states that work done without a permit under Section 14A-4-402 "must still comply with all applicable requirements of the Chicago Construction Codes". Egress sizing, fall protection and energy performance still govern the window that goes in. The full branch-by-branch version of this is on do I need a permit.

Express Permit Program instructions and terms, and the Section 14A-4-402 statement, read at chicago.gov, 2026-08-11.

What the written contract has to contain in Illinois

There is no Illinois contractor license, but there is an Illinois statute, and it is more specific than most homeowners expect. The Home Repair and Remodeling Act, 815 ILCS 513, names windows directly in its definition of covered work, applies to residences of six or fewer units, and excludes "maintenance, service, or repairs under $500".

Section	What it requires	What to do with it at the table
Section 15	Before starting work over $1,000, the contractor "shall furnish to the customer for signature a written contract or work order that states the total cost, including parts and materials listed with reasonable particularity"	Ask for the itemized version before you sign, not after. "Reasonable particularity" is what turns "20 vinyl windows installed" into a list you can hold against another bid
Section 20	The "Home Repair: Know Your Consumer Rights" pamphlet must be given, and over $1,000 a signed Consumer Rights Acknowledgment Form as well	Ask for the pamphlet by name. A firm that has never heard of it is telling you how it runs paperwork generally
Section 22	A buyer age 65 or older has 15 business days to cancel a contract signed at home with a solicitor who was not invited	The single most useful sentence on this page for an older homeowner facing a doorstep close
Section 25	Public liability and property damage insurance of "$100,000 per person and $300,000 per occurrence of bodily injury and $50,000 per occurrence for property damage", unless net worth is at least $1,000,000, plus "$10,000 per occurrence for home repair or remodeling not in conformance with applicable State, county, or municipal codes"	A floor, not a benchmark. The city's floor for a licensed general contractor is higher, starting at $1 million per occurrence at Class E
Section 35	Enforced by the Illinois Attorney General or a State's Attorney. A violation is a violation of the Consumer Fraud Act	Where a complaint goes, since no licensing board exists to complain to

Illinois Home Repair and Remodeling Act, 815 ILCS 513, Sections 10, 15, 20, 22, 25 and 35, read at ilga.gov 2026-08-11. Class E insurance floor from the City of Chicago Department of Buildings General Contractor License page, read 2026-08-11.

The honest limitation: no agency issues anything under this Act, there is no registry, and you cannot look a contractor up against it. It is a set of terms to expect in your paperwork and a route for a complaint afterwards.

Red flags, ranked by what they cost you

Ranked by money and risk, not by how annoying they are. The top four change what you pay or what you are left holding. The rest are signals about how a firm operates.

Red flag	What it usually costs	What to do instead of walking out immediately
No written, itemized contract before work over $1,000	Everything. Without particularity there is nothing to hold anyone to	Ask for the Section 15 contract by name. It is a statutory requirement, not a favour
A permit line nobody can attach to a specific part of the scope	A fee for paperwork that may never be filed	Ask which condition triggers it and which city fee it corresponds to
The window type changes without anyone saying it changes the permit answer	A permit you did not budget for, or unpermitted work	Ask which units are no longer in-kind, and price both versions
No U-factor and no unit count on the quote	Two bids that cannot be compared, so the cheaper one wins by being vaguer	Ask every bidder for the same six lines, in the same order
An "Illinois contractor's license" offered as proof	Nothing directly, but it means the firm does not know its own licensing	Ask instead for the City of Chicago General Contractor License number
Refusal to put the business name and license number in the contract	You may be contracting with an entity that holds nothing	Check the name you were given on the city lookup before signing anything
An insurance expiration date on the city lookup that is close or passed	A license that can inactivate mid-job	Ask for a current certificate sent by the insurer or its agency
"Bonded" offered as if it were a city credential	False reassurance	Ask what the bond covers and who holds it. A bond protecting a lender is not one protecting you
Silence on lead in a pre-1978 house	Dust where children live, and a possible missing city filing	Ask for the firm's renovation certification and search it at the EPA firm search
A price that expires the same evening	The chance to compare, which is the only pricing tool you have	Get the same scope quoted by someone else tomorrow
A deposit with no stated purpose and no milestone attached	Leverage, transferred early	Ask what it buys and when the remaining stages are due, in writing
Tax-credit money promised by the salesperson rather than by the IRS	A budget built on someone else's rules	Ask for the agency page and check it yourself. See below

Rule statements in this table are the ones sourced elsewhere on this page: 815 ILCS 513 at ilga.gov, and the Chicago permit, license and lookup pages at chicago.gov, all read 2026-08-11. The lead row rests on US EPA, Renovation, Repair and Painting Program, read 2026-08-12, which requires certification of anyone paid to disturb painted surfaces in pre-1978 homes and does not specifically name window replacement. The bond row is UNVERIFIED as to whether Municipal Code 4-36-090 imposes a bond in any circumstance, because that code text could not be read.

Answers worth walking away from

Less a blacklist than a translation table. Each of these is something a homeowner can actually hear, and what is wrong with it is specific rather than a vibe.

What you hear	What is wrong with it
"Chicago always requires a permit for windows."	The city publishes a list of window work that does not require one, and most houses in the city fall inside it
"We are licensed by the State of Illinois."	Illinois licenses no general contractor, remodeler or window installer. The state's list of regulated professions carries roofers, architects, engineers, surveyors and home inspectors, and nothing else in construction
"You do not need the paperwork, we will sort it after."	Section 15 requires the written contract before the work starts on a job over $1,000
"The casement is the same thing, it just opens differently."	Different operation is a different type, and the city's in-kind test is "same type, size, and shape". That change is what brings the permit
"We can shave the price by using a smaller unit in the same hole."	Chicago's own permit terms require a replacement to keep at least the same glazing area, and in a residential building at least the same openable area
"Do not worry about landmark, nobody checks."	The Commission on Chicago Landmarks reviews all permit applications on landmark property, and the exemptions "may not apply" there in the first place

Sources as cited throughout: chicago.gov, idfpr.illinois.gov and ilga.gov, all read 2026-08-11.

Pressure at the kitchen table, and the rule that defuses it

Window replacement is sold at home more often than most trades, and a same-day close is the point of a home visit. That is not by itself misconduct. What matters is whether the deadline is real, and it almost never is. Illinois writes one protection directly into the statute: Section 22 of the Home Repair and Remodeling Act gives a buyer age 65 or older 15 business days to cancel a contract signed at home with a solicitor who was not invited. It attaches to the uninvited visit, and it belongs to the older buyer specifically. Everyone else has the simpler protection of not signing.

815 ILCS 513, Section 22, read at ilga.gov 2026-08-11.

For an outside anchor while you are deciding whether a number is even plausible, one publisher reads the Chicago market as $650 to $1,200 per window installed for a standard vinyl double-hung, and $700 to $1,250 per window for an energy-efficient vinyl unit. Source: Modernize, "Window Replacement Cost and Pricing in Illinois (2026)", Isabella Andersen, reviewed by Catie Bonner, updated March 18, 2026, read 2026-08-11. That is one publisher observing a market, not a price list, and it is the only Chicago cost source we found carrying a named author, a named reviewer and a date. Every competing source, shown rather than blended, is on the cost pillar, and the line-by-line version is on what is actually in a quote.

Money a salesperson says you will get back

Energy upgrades attract this pitch, and it is the part of a quote most likely to be wrong by the time you file anything. The federal program usually meant is the IRS Energy Efficient Home Improvement Credit, and whether anything applies to your project turns on the tax rules in force for the year the windows are placed in service.

We publish no amount, cap, percentage or date for it, deliberately. Those change, the IRS owns them, and a number that was right the day it was typed is wrong the day the rules move. The agency's own page is the current version: the IRS Energy Efficient Home Improvement Credit page. Ask the salesperson for that page rather than a brochure, read it yourself, and ask your own tax preparer before any of it enters your budget. A quote whose affordability depends on money from a third party is a quote you should be able to check with that third party first.

Questions a good bidder asks you

The reverse test, and it is quicker than any of the above. A firm quoting your job asks different questions from a firm quoting a job. Listen for these:

• How old is the house? Paid work that disturbs painted surfaces in a home built before 1978 has to be done by a firm certified in lead-safe work practices, and window work commonly disturbs paint. A bidder who asks the age is thinking about that.
• Can I measure each opening? A firm price from the sidewalk is a price for an imagined house.
• What is the sill height in the bedrooms? Chicago's permit terms require opening control devices "that limit the opening to less than 4 inches within 42 inches above the floor when the windowsill is less than 36 inches above the floor". A bidder who asks has read the same rules you have.
• Is the frame sound, or is there rot at the sill? This is the thing that turns a clean install into a change order, and the honest bidder raises it before the deposit.
• What are you actually trying to fix? Draughts, condensation, noise and a sash that will not open are four different problems with four different answers.
• Is the property a landmark, or in a landmark district? A firm that works in Chicago and never asks this has not been paying attention.

Opening control device clause read at chicago.gov, 2026-08-11. Lead certification requirement: US EPA, Renovation, Repair and Painting Program, read 2026-08-12. EPA does not specifically say window replacement is covered.

You may not need any of this

This site is paid a referral fee when a homeowner asks to be matched with a window contractor, set out in full on how we make money. So here are the cases where this page ends your research rather than extending it.

• You may not need most of these questions at all. The Home Repair and Remodeling Act excludes "maintenance, service, or repairs under $500" from its definition, so its contract and pamphlet requirements do not attach to a small job. If one sash has failed, price the repair before you price the house. That decision is worked through on repair or replace.
• You may not need a permit, so the hardest question disappears. In-kind, existing openings, residential building up to four stories above grade, no landmark status: the city's own list says no building permit is required. Nothing to file, nothing to pay, nobody to schedule.
• You may not need new windows. The city's own published position for historic buildings, from the Guidelines for Alterations to Historic Buildings and New Construction, adopted 4 March 1992 and still the published version: "The first and best answer to the question of how to treat windows is not to replace them but rather to retain and repair the existing sash and frames." The same guidelines say weather-stripping single-glazed sash costs little against the price of replacement and can still cut most of the air infiltration. That guidance is written for landmark property and is not a citywide rule, but it is the only place in Chicago's published material where the city weighs repair against replacement, and it points the opposite way from the conversation you are about to have. Quoted in full on the permit page.
• You may not need to ask anyone for a match. Every check on this page runs on a free public city system with no account. If you would rather do it all yourself, the links are above and nothing here is behind a form.

1992 Guidelines and the exemption lists read at chicago.gov, 2026-08-11. 815 ILCS 513 Section 10 read at ilga.gov, 2026-08-11.

What we could not confirm

• Any standard deposit. Nothing read at primary source sets a deposit limit or a customary percentage for Illinois home repair work, so this page publishes no threshold and gives questions instead.
• Whether a surety bond is ever required. Neither Chicago page read states one, and the city's lookup labels its column "Insurance Expiration Date", but Municipal Code 4-36-090 could not be read. Reported as unconfirmed, not as a fact.
• A Chicago permit fee for window work. No attributable amount was readable at the city source on 2026-08-11, so none is published anywhere on this site.
• Which city licence covers a permit-free in-kind swap. Two official City of Chicago pages point different directions on this, which is set out in full on the hiring hub. Asking for the General Contractor License number takes the ambiguity off your table.

Where to go next

• Do I need a permit, for the branch-by-branch version of the exemption lists and the five questions that decide it.
• What is actually in a quote, for the line items that make two bids comparable.
• Landmark buildings and districts, if your address is or might be inside one.
• How we source everything on this site, including what we refuse to publish and why.

Sources

All read on 2026-08-11: the Guide to Building Permits exterior worktype page (both exemption lists, the in-kind definition, the Historic Buildings caveat, the Section 14A-4-402 statement); the Express Permit Program window instructions and its terms and conditions; the Department of Buildings General Contractor License page; the Licensed Trade Contractors lookup and its active-and-inactive version; the IDFPR list of regulated professions; the Illinois Home Repair and Remodeling Act, 815 ILCS 513; the Department of Buildings permit terms for existing buildings; Chicago environmental permitting; the EPA lead firm search; and the Commission on Chicago Landmarks Guidelines for Alterations to Historic Buildings and New Construction, adopted 4 March 1992. Cost band: Modernize, "Window Replacement Cost and Pricing in Illinois (2026)", Isabella Andersen, reviewed by Catie Bonner, updated March 18, 2026. No competitor page, contractor marketing page, directory or search-engine summary informed any statement above.

Straight answers

Questions Chicago homeowners ask

A contractor quoted me a permit line. How do I tell whether it is real?

Ask which specific part of your scope triggers the permit, then check the answer against the city's own list. Chicago publishes work that does not require a building permit, and in a residential building up to four stories above grade it includes "Repairing or replacing (in-kind) an exterior window or skylight in the existing opening". In-kind means "of the same type, size, and shape". So an in-kind swap in the existing openings of a bungalow, two-flat or three-flat that is not landmark property sits on the no-permit list, and a permit line on that quote needs explaining. Where a permit genuinely is required, handling it is real work: the Express Permit Program requires a licensed general contractor on every application. Read at chicago.gov 2026-08-11.

Can I check the license before I sign, and what do I ask for?

Yes, in about three minutes, and ask for two things: the exact business name on the contract, and its City of Chicago General Contractor License number, which begins TGC. Search the business name on the city's Licensed Trade Contractors lookup at webapps1.chicago.gov/licensedcontractors/general, or the generalAll version if nothing comes up, because "not found" and "found but inactive" are different answers. Read both dates in the record, not just one: the license expiration date and the insurance expiration date. The city states that "A general contractor license is automatically inactivated if the associated insurance policy expires". There is no Illinois state contractor license to check, so anyone offering one is describing a credential that does not exist. Read at chicago.gov and idfpr.illinois.gov 2026-08-11.

What does Illinois law require to be in the written contract?

The Home Repair and Remodeling Act, 815 ILCS 513, names windows in its definition of covered work and applies to residences of six or fewer units. Section 15 requires that before starting work over $1,000 the contractor "shall furnish to the customer for signature a written contract or work order that states the total cost, including parts and materials listed with reasonable particularity". Section 20 requires the "Home Repair: Know Your Consumer Rights" pamphlet, and a signed Consumer Rights Acknowledgment Form where the job is over $1,000. "Reasonable particularity" is the phrase that turns "20 vinyl windows installed" into a list you can hold against another bid. No agency issues anything under this Act and there is no registry, so it is terms to expect rather than a credential to verify. Read at ilga.gov 2026-08-11.

The salesperson says a federal tax credit will cover part of the cost. Should I count on it?

Not on a salesperson's say-so. The program they usually mean is the IRS Energy Efficient Home Improvement Credit, and whether anything applies to your project depends on the tax rules in force for the year the windows are placed in service. We publish no amounts, caps, percentages or dates for it anywhere on this site, because those change and the IRS owns them. Ask for the IRS page rather than a brochure, read it yourself at irs.gov, and ask your own tax preparer. A quote whose affordability depends on money from a third party is a quote you should be able to check with that third party before you sign.

Is a large deposit before the work starts normal?

We are not publishing a percentage or a dollar threshold, because nothing we read at primary source sets one for Illinois home repair work, and inventing a number would be worse than saying so. What you can do is ask three questions and read the answers together. What is the deposit for, specifically, and is it tied to ordering your units rather than to the salesperson's visit? What are the remaining payment stages tied to, in writing? And what is the total in the Section 15 contract, itemized "with reasonable particularity"? A deposit attached to a named milestone in an itemized contract is a different thing from a number that appeared on a doorstep.

The price is only valid if I sign tonight. What should I do?

Treat the deadline as information about the seller rather than about the price. Nothing obliges anyone to decide during a visit. Illinois adds a specific protection worth knowing: Section 22 of the Home Repair and Remodeling Act gives a buyer age 65 or older 15 business days to cancel a contract signed at home with a solicitor who was not invited. If a price genuinely will not survive a night, you can also compare it against the same scope from another bidder in the morning, which is exactly what a same-day close prevents. Read at ilga.gov 2026-08-11.

Will you tell me which Chicago window company to hire?

No. We cannot document a ranking, so we publish none, and no contractor is named or scored anywhere on this site. We also do not screen anyone, and this page is not a screening service: every check on it is one you run yourself, on a public government system, in about 10 minutes. What we publish is what is checkable and where to check it. If you want quotes, we pass your details to an independent licensed window contractor working in your part of the city, and we are paid a referral fee by that contractor that never increases what you pay.