Chicago housing stock, and what each type does to a window job

Chicago's housing stock is unusual enough to change what a window job is. More than 80,000 bungalows stand here, close to one third of the city's single-family housing, and two-flats and three-flats make up a quarter of all Chicago housing. Those buildings share three traits that a national window quote does not anticipate: the street-facing opening is usually a group of three or four sash in one frame rather than a single window, the original sash is double-hung or casement, and the opening was built to the house and not to a catalogue size. Almost all of them are also four stories or less, which puts an in-kind replacement in an existing opening on Chicago's list of work needing no building permit. High-rise condos invert every one of those facts. This hub covers all four building types and links the page for each.

Counts from the Chicago Architecture Center and the Chicago Bungalow Association, read 2026-08-11. Permit wording from chicago.gov, read 2026-08-11. How we source, and what we refuse to publish, is on our methodology page.

The four building types, side by side

This is the table to read before a sales visit. It is not about which window is better. It is about what your building physically does to the job, which is the part a national estimate cannot know and a Chicago contractor should.

Building	Usual era	What the street elevation does	Original sash	Where the money goes wrong
Chicago bungalow	1907 to the mid 1930s, depending on the source	A front bay, flat, square, polygonal or curved, carrying a ribbon group of three or four sash inside one architectural frame. Dormer, attic and basement openings elsewhere	Double-hung and casement, art glass common in the bay	Custom sizes. The association's own guidance tells owners not to resize an opening to take a stock frame
Two-flat and three-flat	About 1900 to 1920	Entry porch to one side, a projecting bay of windows on the other, repeated on each floor under a brick or stone cornice	Double-hung	Repetition. One per-opening error multiplies by two or three. Some bays are pressed metal, not masonry
Greystone	1890s to 1910s	Bay again, faced in dimensional Indiana limestone with carved sills, lintels and surrounds	Double-hung	The opening is part of the ornament. Trimming it to a stock size is visible from the street and is not reversible
High-rise condo	Any	Punched openings or curtain wall, repeated identically across the whole elevation	Varies by building	Ownership and height. The window in a perimeter wall is usually not simply yours, and above four stories the permit exemption stops covering upper floors

Bungalow era: the National Park Service documentation form says built in Chicago between 1907 and 1930, the Chicago Architecture Center says 1910 to the mid 1930s, and the Chicago Bungalow Association says 1910 to the mid 1930s. We publish the range rather than pick a pair of dates. Sources read 2026-08-11. The "where the money goes wrong" column is our reading of the sourced facts in each row, labelled as a reading.

Why the opening, not the window, is the Chicago problem

Almost every national window guide is written as though a house has windows, one at a time, in rectangular holes. Chicago's ordinary housing does not work that way, and the difference shows up in the quote.

The front opening is usually a group, not a window

The federal documentation for the type is specific about it. The National Park Service Multiple Property Documentation Form names four bungalow bay forms, flat, square, polygonal and curved, and describes the flat one directly: "When paired with an offset porch, the flat bay generally features one set of ribbon windows in a grouping of three or four windows into a single architectural frame." So the front of a bungalow is commonly one frame containing three or four sash, plus separate dormer, attic and basement openings elsewhere in the building. Counting "windows" on a bungalow is genuinely ambiguous, and two quotes can disagree by a third simply because one counted openings and the other counted sash.

National Park Service, Chicago Bungalows Multiple Property Documentation Form, read 2026-08-11.

The opening was not built to a catalogue

The Chicago Bungalow Association publishes design guidelines for exactly this housing, and its list of things not to do contains the sentence that matters most commercially:

"Enlarge or reduce window openings to fit a stock window frame or change the shape of the window frames."

The same list warns against replacing double-hung or casement windows with fixed picture or slider units, glass block infill on street-facing elevations, sliders in street-facing attic openings, and removing art glass. Read it as a specification rather than as sentiment: bungalow work is custom-size work, and a quote that quietly solves a sizing problem by changing the opening has changed your building, not just your windows.

Historic Chicago Bungalow Association, Design Guidelines dated 6/21/2012, funded by the Richard H. Driehaus Charitable Foundation, read in full 2026-08-11. The association's own windows page carries the same position: "If windows cannot be repaired, replacements should match the historic window as closely as possible."

Art glass sits behind a storm, and the muntins are metal

The Portage Park Bungalow Historic District nomination is unusually precise about how surviving art glass is actually installed: 33 buildings in that district keep their original and art glass windows, and most of that glass "hang behind protective storm windows in the bays of the primary facade, featuring grids of metal muntins, abstracted florals, or Prairie-style motifs". Two things follow. The decorative layer and the weather layer are already separate, so improving the outer one is not an argument for discarding the inner one. And the muntins are metal rather than wood, which matters when somebody prices a "matching grille".

National Park Service, Portage Park Bungalow Historic District nomination, NRHP reference 14000620, read 2026-08-11.

On a greystone the opening is part of the ornament

Greystone openings are cut into dimensional limestone with carved sills, lintels and surrounds. The Chicago Architecture Center notes that much of the limestone in Chicago architecture is Indiana limestone, also called Bedford limestone, a fine-grained light stone "known for its strength, ease of carving and ability to weather gracefully". Because greystones were built as workers cottages, two-flats, three-flats, row houses and larger homes on the same lot pattern, opening sizes are not standardised across the type. Trimming one to accept a stock unit removes carved stone from a street elevation, and that is not something a later owner can put back.

Chicago Architecture Center, Limestone, read 2026-08-11. Greystone three-flats are documented by the city itself, for example "the greystone three-flat at 814 N. Hermitage" in the East Village District designation report, read 2026-08-11.

The four pages under this hub

Chicago bungalow windows

The type that defines the city's single-family stock. More than 80,000 of them stand in what the Chicago Architecture Center calls an arc four to seven miles from downtown, one and a half stories above a basement, brick, with a low-pitched hipped roof, wide overhangs and "generous windows, sometimes with leaded art glass". That page covers the four bay forms and what each does to the opening count, art glass and storm windows, the association's Do and Do Not lists in full, why attic and dormer openings get quoted badly, and how to write a scope that stays inside the city's in-kind definition. It also covers the Chicago Bungalow Association itself, which the City of Chicago Department of Housing states it created, which changed its name from the Historic Chicago Bungalow Association in 2017, and whose membership, as of 2015, is open to owners of all single-family vintage homes built at least 50 years ago.

Two-flat and three-flat windows

The building type that houses a quarter of Chicago. Original completion dates run 1900 to 1918, with an entry porch on one side and a projecting bay of windows on the other under a brick or stone cornice. That page covers what repetition does to a quote when the same bay appears on two or three floors, the pressed-metal bay and why it is a different substrate and a different flashing problem than brick, the original double-hung sash, and the tenant and owner-occupier split that makes phasing a job across floors a real option here in a way it is not in a single-family house.

Greystone windows

Limestone-faced flats and homes, concentrated in areas including North Lawndale, where the Chicago Architecture Center records "greystones with classical limestone details". That page covers carved sills, lintels and surrounds, why openings are not standardised across the type, and the Historic Chicago Greystone Initiative, a partnership of the Chicago Department of Housing, Neighborhood Housing Services of Chicago and the University of Illinois Chicago City Design Center, whose research was carried out in 2004 and 2005. It also states openly that greystone-specific window guidance is thinner-sourced than bungalow guidance, because the initiative's 2009 design guidelines document is image-encoded and its text could not be verified.

High-rise and condo windows

The type where the rules invert. Chicago's permit exemption for in-kind replacement in an existing opening is written for "a residential building up to 4 stories above grade", so an upper-floor unit in a high-rise is outside it, and the Express Permit Program covers a building up to seven stories, or taller only with drawings prepared by an Illinois-licensed architect or structural engineer. Before any of that, ownership has to be settled: under the Illinois Condominium Property Act the default treats a window in a perimeter wall as a limited common element, and the declaration can override the default. That page walks the statute, the declaration, and the order to do things in.

Landmark status is two different things, and only one of them restricts you

This is the most common confusion in Chicago vintage housing, and getting it wrong costs money in both directions: people abandon a sensible plan because they think a district forbids it, or they order windows for a building that genuinely does need city review.

National Register listing restricts nothing by itself. The National Park Service states: "Under Federal Law, the listing of a property in the National Register places no restrictions on what a non-federal owner may do with their property up to and including destruction, unless the property is involved in a project that receives Federal assistance, usually funding or licensing/permitting." A homeowner in one of the 15 National Register bungalow districts does not need federal permission to change a window.

Chicago Landmark designation does restrict. The city states that its Historic Preservation Division "reviews all permit applications for work involving designated and proposed Chicago landmarks and landmark districts". The city's pre-permit document is broader: the Commission reviews all permit applications for "alteration, construction, reconstruction, erection, demolition, relocation, or other work" on a designated or proposed Chicago Landmark or anything "located within a designated or proposed Chicago Landmark District", and "The Department of Buildings routes building permit applications to Commission staff for review as part of the building permit process". Submission requirements for alteration work include "Information on proposed exterior features, such as windows, doors, skylights, garage doors, railings, exterior materials". Designation reports then define what is protected. For the East Village District the recommended significant features were "all exterior building elevations, including rooflines, visible from public rights-of-way", which puts a street-facing window squarely inside review.

Building type	National Register district likelihood	Chicago Landmark district likelihood
Bungalow	Meaningful. 15 named bungalow districts across the Bungalow Belt	Low on what we could read. No bungalow district appeared among the named Chicago Landmark districts we reviewed
Two-flat and three-flat	Present inside neighbourhood districts	Real. The East Village District is a designated example of a two-flat and three-flat neighbourhood
Greystone	Present inside neighbourhood districts	Real, by the same mechanism
High-rise condo	Present	Real. Both "860-880 Lake Shore Drive" and the "East Lake Shore Drive District" appear on the city's Chicago Landmarks list

National Register list read at chicago.gov, "Chicago Listings on the National Register of Historic Places, as of October 31, 2025". Landmark rows read at the city's Chicago Landmarks listings page, which itself states that it lists "just a portion of the designations", so the bungalow row is our reading of an incomplete published list and not a determination about your address. All read 2026-08-11.

The 15 National Register bungalow districts

Listed under the Chicago Bungalows Multiple Property Submission and confirmed against the city's own National Register list: Auburn Gresham, Avalon Park, Brainerd, Falconer, Gage Park, Hermosa, North Mayfair, Portage Park, Rogers Park Manor, Schorsch Irving Park Gardens, South Park Manor, South Shore, Talman West Ridge, West Chatham and Wrightwood. Listing dates run from February 25, 2004 (Schorsch Irving Park and South Park Manor) to August 23, 2023 (Avalon Park).

One conflict, recorded rather than hidden. chicago.gov dates the Brainerd listing December 27, 2016; the Chicago Bungalow Association says January 6, 2017. We prefer the city. Nothing about a window job turns on it, but a site that quietly picks between two disagreeing sources is a site you cannot audit.

City of Chicago National Register list and the Chicago Bungalow Association district page, both read 2026-08-11. Full detail on how landmark review actually works is on the landmark districts page.

The four-story line runs straight through Chicago's housing stock

Chicago publishes two separate lists of work needing no building permit. In any building, only a ground-level window may be replaced in kind without a permit. The broader exemption, covering an in-kind replacement in an existing opening at any floor, is written only for "a residential building up to 4 stories above grade or an associated accessory building (such as a garage) on the same lot". The city defines in-kind as replacement "using new materials, objects, or elements of the same type, size, and shape".

Line that up against the stock on this page and the split is clean. A bungalow is one and a half stories above a basement. A two-flat, a three-flat and a greystone flat building sit at two or three. All of them are on the right side of the line, at every floor. A high-rise is not, above the ground floor. That single fact is why three of the four pages under this hub are mostly about the building and the fourth is mostly about permission.

Building	In-kind swap, upper floors	In-kind swap, ground level
Bungalow, two-flat, three-flat, greystone	On the exemption list	On the exemption list
Residential building of five stories or more	Not on the list, so the permit route applies	On the list, where no part of the exterior wall is cut away
Landmark property or a landmark district, any height	The city says its exceptions "may not apply". Settle this before anything else

City of Chicago, Guide to Building Permits, work not requiring a building permit, exterior, read 2026-08-11. The full rule, the in-kind definition and the exceptions are on the permits hub and do I need a permit.

Who owns the window in a condo

In a high-rise the first question is not which window to buy. It is whether the window is yours to buy. The Illinois Condominium Property Act sets a default and then lets your building override it, and the override is the part most owners never read.

• The default is stated with a qualifier. Section 4.1(a) opens "Except to the extent otherwise provided by the declaration or other condominium instruments". Everything below is subject to that.
• Windows in perimeter walls are common elements by default. Section 4.1(a)(2) gives the unit the finished surfaces of a perimeter wall, "while all other portions of such walls, floors or ceilings and all portions of perimeter doors and all portions of windows in perimeter walls shall be deemed part of the common elements".
• And they are limited common elements. Section 4.1(a)(5) deems windows in perimeter walls, along with shutters, awnings, balconies, patios and similar features serving a single unit, "a limited common element appertaining to that unit exclusively". Section 2(e) confirms common elements include limited common elements unless otherwise specified.
• The board's default duty covers common elements. Section 18.4(a) makes the board responsible "To provide for the operation, care, upkeep, maintenance, replacement and improvement of the common elements".
• Your declaration is the document that actually answers it. Section 4(g) requires the declaration to contain "A description of both the common and limited common elements, if any, indicating the manner of their assignment to a unit or units". Many declarations assign window cost to the unit owner, which is lawful and common.

Illinois Condominium Property Act, 765 ILCS 605, full text as effective January 1, 2023, published by the Illinois Department of Financial and Professional Regulation, read 2026-08-11. This is a general description of a statute, not legal advice. Read your own declaration, and if it is ambiguous, ask a lawyer rather than a salesperson.

The recommendation. In a condo, get the declaration and the board's written position before you take a single measurement. In a bungalow, two-flat, three-flat or greystone, settle the landmark question first, then write your scope in the city's own vocabulary: same opening, same type, same size, same shape. Those two sentences prevent most of the expensive surprises on this page.

You may not need new windows at all

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 it is worth being direct about the cases where the honest answer is to do less.

• The guidance written for this housing puts repair first. The Chicago Bungalow Association's Do list is retain and repair original frames, maintain the historic muntin and grille pattern, restore or recreate art glass, and add thin profile wood or metal storm windows and screens "similar in size, shape and color to existing windows". That is a maintenance path, not a replacement path, and it is what the organisation the city created recommends for the city's most common house.
• A storm window needs no permit anywhere in Chicago. Installing, maintaining or removing a storm window or an insect screen is on the city's no-permit list for any building at any height. So is repairing damage to an existing window, and replacing the glass in an existing sash. If one unit failed, that is a repair, not a whole-house project. See storm windows.
• Your art glass is probably already protected. The Portage Park nomination records art glass hanging behind protective storm windows in the primary facade bays. If that describes your bungalow, the sensible upgrade may be to the storm layer.
• Some of this work is genuinely reversible and the city treats it that way. In the East Village District designation report, replacement of original double-hung sash with later sash is classed among "changes considered minor and reversible", unlike the loss of a cornice. That is a landmark-district judgement rather than a rule for every building, but it tells you where the irreplaceable value sits, and it is usually not the sash.
• If the question is repair or replace, price both. The economics are worked through on repair or replace, and the sash types involved are covered on double-hung and casement.

Chicago Bungalow Association design guidelines, the Portage Park nomination, the East Village District designation report and the city's no-permit list, all read 2026-08-11.

What we could not source, and will not guess

Five things a reader might reasonably expect on a page like this are missing on purpose, because we could not read them at a source we would stand behind.

• How many greystones Chicago has. A figure of roughly 30,000 circulates widely. We traced it only to Wikipedia and commercial blogs, and found no city, university, museum or Census source carrying it. A neighbourhood-level count for North Lawndale appeared only in a search summary. Neither is published here.
• When the bungalow association was founded. Secondary sources give a year and a mayor. The city's own page, which states that the Department of Housing created the organisation and that it changed its name in 2017, gives no founding year, and no authoritative source was found. So we publish the facts the city states and not the year.
• How many Chicago Landmark districts and individual landmarks exist today. The city's open data portal answers, but its landmark districts dataset reports a last-updated date in 2011 and its most recent designation is from 2009. A stale count published as a current one is exactly the kind of number this site exists not to repeat.
• What share of Chicago housing is in high-rise or larger multi-unit buildings. Census units-in-structure data would size it properly. The Census API now requires a key and returned a missing-key error on every call, so nothing on this page claims a high-rise share.
• A greystone-specific window guideline. The Historic Chicago Greystone Initiative published design guidelines in 2009, but the document is image-encoded and its text could not be verified. Greystone sash specifics on this site are therefore thinner sourced than bungalow specifics, and the greystone page says so on its face.

What any of this costs

No dollar figure appears on this page, and that is deliberate. This site publishes a price only with the source it came from and the date it was read, and no Chicago price was read at a primary source for this pillar. A custom-size bungalow bay, a repeated three-flat bay and a high-rise unit governed by a declaration are three different cost problems, and one range covering all three would be worse than no range at all.

Read the cost pillar, which attributes every figure it publishes and says plainly where it has none, and what is actually in a quote, which is what lets you compare two estimates describing different scopes. When you collect quotes, make every contractor price the same written scope: the same opening count, sash type, sizes, and the same answer on storms and art glass.

Sources

All read 2026-08-11. Chicago Architecture Center: Chicago Bungalow, Two- and Three-flats, The tale of the Chicago two-flat, Limestone. Chicago Bungalow Association: the type, windows, current bungalow historic districts, and its Design Guidelines dated 6/21/2012. National Park Service: Chicago Bungalows Multiple Property Documentation Form, Portage Park Bungalow Historic District nomination, National Register FAQs. City of Chicago: Historic Chicago Bungalow Initiative, East Village District designation report, National Register listings, October 31, 2025, landmarks permit review, work not requiring a building permit, Express Permit Program, window and door replacement. Illinois: Condominium Property Act, 765 ILCS 605, effective January 1, 2023. No competitor page, contractor blog, retailer page or search-engine summary informed any statement above.

If you want quotes to hold against these answers, the form below passes your details to an independent licensed window contractor working in your part of the city. What that relationship is, and is not, is set out on the about page.

Straight answers

Questions Chicago homeowners ask

Does a Chicago bungalow need custom-size windows?

Usually yes, and the association set up by the city says so in its own guidance. The Chicago Bungalow Association design guidelines list, under things not to do, "Enlarge or reduce window openings to fit a stock window frame or change the shape of the window frames". The bungalow front is normally a band of three or four sash inside one architectural frame, sitting in a flat, square, polygonal or curved bay, so the opening was built to the house rather than to a catalogue. That is the single most commercially relevant sentence in the whole document, because a quote priced on stock sizes and an opening that does not accept stock sizes are two different jobs. Design guidelines dated 6/21/2012, read 2026-08-11.

My block is in a National Register historic district. Do I need permission to replace my windows?

No, not from the federal government. The National Park Service states it plainly: "Under Federal Law, the listing of a property in the National Register places no restrictions on what a non-federal owner may do with their property up to and including destruction, unless the property is involved in a project that receives Federal assistance, usually funding or licensing/permitting." It repeats the point: "Listing in the National Register places no federal restrictions or requirements on a private property owner. You may do with the property as you wish, within the framework of local laws or ordinances." Those last words are the catch. Local law is a separate question, and in Chicago that means Chicago Landmark status, which is not the same designation. Read at nps.gov, 2026-08-11.

What is the difference between a National Register district and a Chicago Landmark district?

One is a federal honour roll, the other is a local permit rule. National Register listing imposes nothing on a private owner. Chicago Landmark designation does: the city states that its Historic Preservation Division "reviews all permit applications for work involving designated and proposed Chicago landmarks and landmark districts", and the Department of Buildings routes permit applications to Commission staff as part of the normal building permit process. Submission requirements for alteration work include "Information on proposed exterior features, such as windows, doors, skylights, garage doors, railings, exterior materials". The two designations can overlap on the same building, so the answer for your address is not one lookup. Read at chicago.gov, 2026-08-11.

My bungalow has art glass in the front bay. Do I have to lose it?

No, and losing it is what the guidance tells owners to avoid. The Chicago Bungalow Association design guidelines list "Remove art glass windows" among the things not to do, and list "Restore or recreate art glass windows" and "Add thin profile wood or metal storm windows and screens similar in size, shape and color to existing windows" among the things to do. There is a practical detail worth knowing before anyone quotes you. A National Register nomination for the Portage Park Bungalow Historic District records that most surviving art glass in that district "hang behind protective storm windows in the bays of the primary facade, featuring grids of metal muntins, abstracted florals, or Prairie-style motifs". So the art glass and the weather protection are already two separate layers, and upgrading the outer layer does not require sacrificing the inner one.

Who owns the window in a Chicago condo, me or the association?

The declaration for your building answers it, and the statute only sets the default. Under the Illinois Condominium Property Act, section 4.1(a) opens with "Except to the extent otherwise provided by the declaration or other condominium instruments", and then treats "all portions of windows in perimeter walls" as part of the common elements, while section 4.1(a)(5) deems windows in perimeter walls a limited common element assigned to that unit exclusively. Section 18.4(a) gives the board the duty "To provide for the operation, care, upkeep, maintenance, replacement and improvement of the common elements". So by default the window is not simply yours, but the declaration overrides the default and many declarations push the cost onto the unit owner. This is a general description of the statute and not legal advice. Read the full act as effective January 1, 2023, published by the Illinois Department of Financial and Professional Regulation, 2026-08-11.

Is a two-flat window job different from a bungalow job?

Yes, mostly in repetition and substrate. The Chicago Architecture Center describes the type as having "an entry porch to one side, and a projecting bay of windows on the other", with the bay repeated on each floor, so a per-opening measuring error multiplies by two or three rather than happening once. Some bays are not masonry at all. A City of Chicago landmark designation report for the East Village District cites "fine architectural details such as pressed-metal bay windows, cornices, and gracious entries", and a pressed-metal bay is a different substrate and a different flashing problem than brick. The original sash is double-hung: the same city report notes that "Some original double-hung window sash has been replaced with later double-hung or single-pane sash". Read 2026-08-11.

How many bungalows and two-flats does Chicago actually have?

Two authoritative publishers agree on the bungalow figure. The Chicago Architecture Center states Chicago "has more than 80,000 bungalows, which make up 1/3 of our city’s single-family housing stock", and the Chicago Bungalow Association independently states over 80,000 remain, nearly one third of the single-family stock. For flats, the Chicago Architecture Center states that "Two- and three-flat apartment buildings make up a quarter of Chicago’s housing", and separately that two-flats "along with their larger cousins the four-flat and six-flat, make up more than 30 percent of our city’s housing stock". Those are two different groupings and we do not blend them into one number. Both read 2026-08-11. No Census or city tabulation of bungalows specifically was found.