There were several concerns over the Chicago Building Code (CBC) 2019 code requirement of 2 exits out of a residential unit over 1250 sq. ft. that was included in a stealth code amendment a few months ago. This triggered several redesign efforts in proposed residential high-rise towers. As we worked with design teams and developers, it was difficult to make the layouts of these units work. Previously the building code mandated two exits out of units that were over 2500 sq. ft. The extra exit in a 1250 sq. ft. unit would require at least 3% of the floor area, and as it is carried through over several hundred units, projects will not pencil out.
The Chicago's Department of Buildings (DOB) has heard our community's concerns and adjusted the maximum size of the unit in most cases to be 2500 sq. ft! This will allow more flexibility in designing residential units.
Here are more code details:
- The maximum number of occupants in a fully sprinklered residential unit has been increased to 20 occupants (2,500 sq. ft.) in a fully sprinklered building. This was addressed by revising Section 1006.2.1, Exception h, to allow for additional occupants. In non-sprinklered buildings, dwelling units are still limited to 10 occupants (1,250 sq. ft.). This change has not yet been updated in AMLegal or any of the ICC websites. We will provide updates when that happens, however, the approved ordinance (SO2021-3239) is available on the Chicago City Clerk’s website.
- Additionally, the Chicago City Council approved the mechanical code updates that were summarized in our blog post. We are excited to see these updates be accepted, allowing for a greater range of systems and devices, as well as modernizing what refrigerants can be utilized in Chicago.
- Accessible units are now explicitly required to be distributed proportionally throughout the building to provide a variety of sizes and locations and affordable and market-rate units. We will review this change with MOPD to determine what impacts this will have on the distribution of accessible units in buildings.
These code updates highlight the flexibility of the new modern code, that as changes are made to maintain the life safety of the occupants if there are any unintended consequences of these changes, the code can be easily updated and revised to address any issues that may arise.