Tag: building code

Chicago’s zoning code doesn’t allow five (or more) roommates

Can you guess how many people the Chicago zoning code allows living together in a typical apartment or house when all of them are unrelated to each other?

  • 2
  • 4
  • 3
  • 5
  • 6
  • 7 or more

The answer is in the following paragraph.


The Chicago zoning code allows an unlimited number of related people to live together along with three unrelated people. If you’ve got roommates and none of you are related, the zoning code says that there can be only four of you in a dwelling unit. (There are alternatives to this scenario which are not part of the discussion, comprising shelters and congregate housing and group living, which are separately defined and exclusive of a typical “roommate” scenario.)

If you want to have four roommates you may need a five-bedroom house, which you could easily find in Chicago and go ahead and rent, you’ll be fine. The city will not enforce the zoning code in this situation.

The city’s planning and buildings departments will, however, enforce the zoning code at the time of a Planned Development or building permit application if the proposal is for an apartment building (likely marketed as a co-living situation) with five-bedrooms apartments. I’m aware of two such proposals happening in Chicago; one of the proposed projects is under construction but was modified prior to approval to have only four-bedroom apartments.

How the zoning code regulates occupancy limits in housing

The Chicago zoning code has two definitions (or “defined terms”) that have to be read together to understand how the limitation works.

17-17-0248 Dwelling Unit. One or more rooms arranged, designed or used as independent living quarters for a single household [a defined term, see below]. Buildings with more than one kitchen or more than one set of cooking facilities are deemed to contain multiple dwelling units unless the additional cooking facilities are clearly accessory and not intended to serve additional households.

17-17-0270 Household. One or more persons related by blood, marriage, legal adoption or guardianship, plus not more than 3 additional persons, all of whom live together as a single housekeeping unit; or one or more handicapped persons, as defined in the Fair Housing Amendments Act of 1988, plus not more than 3 additional persons, all of whom live together as a single housekeeping unit.

None of the terms in the household term are themselves defined terms in the zoning code, so a “single housekeeping unit” would take the definition from the “latest edition of Merriam Webster’s Collegiate Dictionary”, or as interpreted by the zoning administrator.

Most apartments, and especially apartments marketed and used as “co-living” are considered dwelling units. Thus, each apartment can comprise one household and one household can comprise a single housekeeping unit and a single housekeeping unit can comprise an unlimited number of related people and up to three unrelated people.

However, there is an exception that an unlimited number of unrelated “handicapped persons” can live with up to three unrelated people.

Why occupancy limits don’t belong in zoning codes

Occupancy limits based on family relationship and familial status arose when parts of cities were becoming overcrowded during an era of industrialization and moving to cities (urbanization). I’m not going to elucidate this point but direct readers to the history described in “Full house: occupancy standards, normative zoning, and the responses of US cities to changing households” by Amarillys Rodriguez.

Putting occupancy limits in zoning codes instills moral values that are outdated, maintain segregation, and fail to respond to changing norms, family development patterns (think “chosen family” households), and having the choice to decide who one wants to live with. In fact, it may be “virtually impossible to satisfactorily define family, or develop an alternative to the term, in a manner that satisfies the competing
goals of maintaining privacy, allowing freedom of association, and protecting
community ‘character’ (itself a loaded term)” (Sara Bronin, “Zoning by a Thousand Cuts”)

In Nolan Gray’s terms, zoning standards like this are based on “elite norms and heuristics”. (A heuristic is a problem-solving technique used when devising an optimal solution or assessment is impractical.)

Occupancy limits, if there are any, should be based on demonstrated facts that show benefits or pitfalls of numerically limiting who and how many people can live together. A building code that’s based on ensuring occupants’ safety is likely where that can be achieved and regulated; I’ll discuss what the Chicago Building Code has to say about occupancy limits in the next section.

Colorado Governor Polis recently signed a law that strips municipalities of the power to set occupancy limits that aren’t based on reliable information about the safety of the number of people in an apartment.

An excerpt from Colorado House Bill 24-1007; it reads, “(3) a local government shall not limit the number of people who may live together in a single dwelling based on familial relationship. Local governments retain the authority to implement residential occupancy limits based only on: (a) demonstrated health and safety standards, such as international building code standards, fire code regulations, or Colorado department of public health and environment wastewater and water quality standards;”

Chicago building code sets a kind of occupancy limit

If Chicago – or Illinois – were to adopt a law similar to Colorado’s the existing Chicago Building Code would regulate the design of an apartment. It does not set a maximum, though.

Jamin Nollsch, a senior architect at UrbanWorks who analyzed the code on my behalf, said “For the purposes of discussion, the Chicago Building Code says that at least eight people could occupy a 1,000 sf apartment. The code commentary makes it clear that the 125 s.f. per occupant load factor for apartments is a design mechanism for the egress system, and not an absolute maximum.

“There are many code sections that set limits on the occupant load of an apartment, whether it is the 7 s.f. per occupant limit, or 10 occupants for spaces with 1 exit, or the width of the egress doors. The occupant load factor, however, is intended to be a design factor and not a maximum. With approval from the building official, the maximum number of occupants can be as high as the egress design allows.”

In other words, if an apartment can be designed with a sufficient number or size or type of exiting paths, there is not really a limit to the number of people who the building code indicates could safely occupy the apartment.

Do you think the Chicago zoning ordinance should be amended to defer to the building code in setting occupancy limits?

Why courtyard buildings aren’t allowed in Chicago anymore

Chicago Urbanist Twitter was abuzz this month when renderings of a proposed construction courtyard building were published (they’re shown below), given that the historical building typology hadn’t been built in Chicago in decades. Some wondered if this revered local design was making a return.

The post is probably better titled “how it is that courtyard buildings aren’t built in Chicago anymore” as I don’t know why the codes changed in such a way to, effectively, do away with the housing typology. And it’s the second time I’ve evaluated the feasibility of building a specific housing typology; see my post about cottage clusters.

I don’t think there will be a resurgence or resurrected trend in building courtyard buildings in Chicago, because of how the city’s building and zoning codes inhibit them. At the end I discuss how Chicago might get courtyard buildings to return.

Chicago has several variations of courtyard buildings

Common variations of Chicago courtyard buildings include:

  1. Large inset front courtyard (U-shaped) buildings
  2. Buildings with rear courts, often with exterior unenclosed porches or a small rear yard and possibly a garage (I speculate providing a space for one or two cars in a 20-unit building was meant for the building owner)
  3. Side court buildings
  4. S-shape and multi-court (which are kind of modular)

People like Chicago courtyard buildings

To describe the Chicago courtyard building, I compiled reasons why people like courtyard buildings, especially the type with the front courtyard based on conversations I observed on Twitter and by asking members of Urban Environmentalists of Illinois.

  • They look nice, with all of the landscaping visible from the sidewalk. Landscaping isn’t relegated to the roof and can be seen by the public.
  • Everyone’s unit has a designated nice view, as every unit faces the inner court. Compare this to a double-loaded corridor where about half the units will face the street and the other half may face the alley.
  • The unit layouts are some of the best; the apartments have lots of natural light and all rooms have windows. The units are often “dual aspect” and with windows on two walls the unit can have cross ventilation. This may be a subjective, though, as the use of constant mechanical air flow with filtering and exhausting may provide some with greater comfort. Additionally, the need for cross breeze is less necessary given air conditioning and low-cost energy.
  • Courtyard buildings enable many different unit types within one development (studios and 1-3 bedrooms), which means there can be a decent mix of types of people (families and singles and couples.) This is unlike a building using a double-loaded corridor floor plan, which often place multi-bedroom apartments at the corners.
  • Most units are pretty quiet since some of the unit’s layout is not directly against street, not too noisy.

Learn more about floor plan design significance by listening to this Odd Lots podcast interview with Stephen Smith and Bobby Fijan.

I also feel that a courtyard by building’s layout is similar to a point access block’s (i.e. two or three units per floor per stairwell). Even though the courtyard buildings can be large, their multiple cores help them appear “small-scale and homey compared to having long hallways. You actually know people in your stairwell, not a bunch of strangers” (Jesse O.). (This also means they utilize space more effectively than double-loaded corridor buildings, which has impacts on cost.)

Mike Eliason is a major proponent and promoter of point access blocks because they offer a superior layout; his book, to be published this year, will argue that, but you can get a preview of his reasonings by reading through his Twitter (like this tweet) or reading the point access block policy brief that his architecture firm wrote for the City of Seattle.

If you’d like to learn more about the courtyard building’s history, Moss Design, a local architecture firm, explores the advantages and history of courtyard buildings in Chicago (the post is from 2014).

What do you like about courtyard buildings?

Zoning code conflicts

Courtyard buildings are difficult or impossible to build in Chicago for many of the reasons that I described in a previous post about how to amend the zoning code to allow “cottage courts” in Chicago. They are repeated here:

  1. Rear setbacks would need to be reducible, preferably without the need for a variation from the Zoning Board of Appeals. Because the houses are oriented to face a common green space at the interior of the lot (not at the front or rear of the lot), the rear of the house may be close to the rear property line, violating the rear setback standard of ~30 feet. 
  2. Side setbacks would need to be combinable or eliminated as a requirement for courtyard buildings because the unbuilt space on the property that is normally required for a rear yard is concentrated in the interior court pushing the building to the edges of the property.
  3. Parking requirements would need to be more flexible, both in quantity and in design, otherwise the parking areas would occupy a third to half of the property, minimizing the space that can be used for the interior court. To maximize the shared green space, parking requirements should be reducible for this housing type. The Chicago TOD ordinance that reduces parking requirements may be relevant here, as it now applies in RM-5, and higher, residential zoning districts (notably rare).
  4. Minimum lot area per unit standards can likely be met cost-effectively in the less common RM-5 and higher zoning districts. The most common residential zoning districts in Chicago are RS-3 and RT-4. The RS-3 zoning districts do not allow more than two units on a lot; in RT-4 zoning districts the developer would have to assemble so many lots to be able to get the unit count necessary to make such a building’s construction cost-effective yet the land acquisition might be so costly as to make the project infeasible.

Walk around Rogers Park, Lakeview, and Hyde Park – where it seems the most courtyard buildings were built – and you’ll see that most of them don’t have any car parking. And the ones that do certainly don’t have as many to meet current car parking requirements.

Building code conflicts

Note that “IANAA” (I am not an architect) and my expertise on building codes is always quite limited.

Exits and stairs. The Chicago building code generally requires a minimum of two stairs for buildings of an occupancy classification of R-2 (multifamily with four or more units, not including shelters); see section 1006.3.2 in the Chicago building code for info about two-exit standards.

The two exits must also be within a minimum and maximum distance apart from each other; this standard ends up requiring a corridor between the two stairs so that each unit can access either stair. This corridor eliminates rentable area and decreases the floor plan’s efficiency (a metric for architects and developers that affects the pro forma).

In the new construction courtyard building’s renderings at the top of the post, there are three interior stairs! See also the Standard 8-3 comment below.

Section 1006.3.3 in the Chicago building code outlines the single exit (single stair) conditions. Without going further into alternatives and exceptions, a three-floor three-flat can be a single stair building as long as the third floor doesn’t exceed 1,600 s.f. of floor area and the house has a sprinkler system ($$). You read that right…Chicago allows single stair for buildings with 1-3 units and 1-3 floors.

Existing courtyard buildings in Chicago that don’t have a second interior exit stair will then have an exterior exit stair, often connected to porches; this example has a minimal shared porch attached to the exterior exit stair at a courtyard building.

There are limitations on the use of exterior stairs for exiting requirements and I’m unable to articulate their impact on size or orientation. They cannot be used for exiting on floors that are 45 feet above grade, and cannot provide “more than 50 percent of the number and minimum width or required capacity of means of egress components” (1027.2.1). There are also standards on the exterior stair materials.

Long corridor. The minimum corridor length and the sometimes-extra stairs require a bigger building footprint (increasing construction cost compared to a building without corridors, like the point access block), which is already constrained by parking mandates and inexplicable zoning code setback requirements. See section 1007.1.1 in the Chicago building to learn about how far apart exits need to be.

It’s not actually the multiple stairs that are the space hog…it’s the corridor that’s required to connect the multiple stairs.

Setbacks. Fire separation distance is different than a zoning setback. The building code allows buildings to abut (touch) adjacent buildings but the fire protection standards on that side of the building are increased. No windows could be built on a wall that has zero setback, so natural light and vent requirements for bedrooms would have to be provided through light courts and placing bedrooms at the front or rear of the building.

A quick note about elevators: it’s my understanding that an elevator is not required if the required accessible Type A units (20 percent) are at grade and no floors above the ground floor contain building amenities (1104.4).

Do you know of some other regulatory standards that affect the development feasibility of courtyard buildings and point access blocks in the United States?

Return of the courtyard building in Chicago?

As I said at the beginning, I don’t think the one proposed new construction courtyard building will lead the resumption of the courtyard building in Chicago. There are the conflicts in the codes that I think would need to be significantly modified to facilitate new courtyard building construction.

I also believe that there are other factors: who develops, who designs, who lends, and who would live there that matter. These may be more influential in whether a new courtyard building gets built in 2024 than the zoning and building code conflicts; in other words, what if the city tweaks those codes and no new courtyard buildings get built?

I’m thinking of the “Standard 6-3” building I promoted, a typical design in Chicago that was re-legalized in some areas of the city when the Connected Communities Ordinance was passed in 2022. That zoning code amendment allows for a six-flat (back to back apartments on three floors) to be built on a standard size lot with minimal or no car parking. To my knowledge, though, none have been built.

Then there’s the circumstance that the double loaded corridor makes a lot of financial sense for developers and construction companies; the identical unit layouts are easy to design and build and the density of units is quite high. Plus the floor plate efficiency is significantly higher in a DLC compared to a single-loaded corridor (which Chicago has some of, in the form of “California style” apartments). DLC buildings often have a much greater proportion of studios and one-bedroom units, which, on a per-square-foot basis, collect more rent than larger units.

To comment on those factors of developer, designer, lender, and tenant, I would defer to asking those people, which is beyond the scope of this blog post. Conveniently, a developer of smaller-scale multifamily buildings, Coby Lefko, wrote a guest article on Noah Smith’s blog that I think addresses some of the friction to develop something like a courtyard building.

Coby writes, “Even while recognizing the need for comprehensive solutions, too many urbanists have ignored the importance of finance [emphasis added] in charting a different course for the future.” The thrust of the article is that cities need small developers but it’s hard to be a small developer.

I think many urbanists, myself included, opine on development in ways that fail to reflect lacking the knowledge of experience of having actually built something. I’m trying to gain more knowledge about it; recently, I nominally learned how to read and write a pro forma, a special spreadsheet that developers use to gauge the cost and benefit of a specific proposal.

As more of us consider land use reforms to allow for housing abundance in Illinois, let’s also discuss “supporting new courtyard buildings” – they provide desirable unit layouts, small and family-sized apartments, cozier neighbor arrangements, and Chicagoans just really like them!