The Chicago Department of Buildings has announced a new pilot program regarding the use of mechanical only ventilation for residential units in high rise buildings. The intent of this program is to test using portions of the 2024 International Mechanical Code (IMC) in Chicago. This program is limited to the following types and sizes of projects:
- Construction of a new R-2 occupancy building in new high-rise building (over 80’-0” in height)
- Conversion of space in an existing high-rise to R-2 Occupancy
- Rehabilitation/Renovation of an existing R-2 occupancy in an existing high rise building
If approved to participate in this program, projects will be permitted to follow the memorandum linked here, instead of what is required for typical projects in CBC Section 14B-12-1202.1, exception 2, and Table 18-28-403.3 of the Interim Chicago Mechanical Code. These requirements should be carefully reviewed by the Mechanical engineer for the project and confirm that the design requirements can be met.
Requests to participate in the program will be submitted through the Alternative Code Approval Relief (ACAR) process, and which requires a $150.00 submission fee to be paid prior to submission. Within 1 week of the submission DOB will reach out to schedule a presentation and interview, or to request additional information. After the interview and presentation, a response from DOB should be issued via email within 5 business days with an approval or a denial. Note that the fee is required to start the process, and is not refunded if the project is denied. The request to participate in the program must be submitted on the Pilot Program ACAR Form, the standard ACAR form will not be accepted.
The mechanical ventilation and exhaust systems in all areas where work is occurring as a part of the project must be designed in accordance with any comments or other project specific conditions that are identified or raised as a part of the ACAR process.
Additionally, as a part of the request to participate in the program, the project team must provide documentation that the project complies with the following requirements:
The entire building must be fully sprinklered
Each dwelling unit must fully comply with the requirements for natural light per CBC Section 14B-12-1204.2, with no variances.
No combustion or solid fuel burning appliances may be within the dwelling units.
Each story with a residential occupancy must comply with CBC Section 14B-4-403.4.7 of regarding smoke removal in post-fire salvage and overhaul operations.
The interview and presentation that will be required is a 1 hour long meeting and can be held either virtually or in person. The Architect of Record, any Engineers of Record that will be stamping mechanical drawings in the project, and a representative of the Developer must attend the meeting. The presentation must address at a minimum:
How the proposed design will meet all design and program requirements.
What the projected operating cost of the mechanical system will be for each type of unit on a winter design day and summer design day (assuming 16 ¢/kWh and 65 ¢/therm), and what measures have been taken in the project to reduce the operating cost.
How the proposed building and mechanical design addresses maintaining habitable conditions in units during an extended power failure on a summer design day, winter design day, and a spring or fall transitional day.
Any additional features of the mechanical system design that exceed the code minimum requirements, such as additional measures to enhance indoor air quality or occupant comfort.
If the project is accepted into the pilot program, during construction it must pass rough and final inspections by a City Ventilation Inspector. Additionally, all mechanical ventilation and exhaust equipment must be commissioned per Section C408 of the Chicago Energy Transformation Code (CETC). Note that the DOB may require a draft commissioning plan be submitted for approval as a condition of acceptance into the pilot program.
This pilot program is in effect from November 27, 2024 through June 30, 2025, however the Building Commissioner may change or end the program at any time prior to the scheduled completion.
Please see the below links to the memorandum announcing this pilot program, as well as the appendix here.
Announcement
Pilot Program ACAR Form
Memo
Appendix