Identify each Chapter 4 condition the building has, such as a high-rise, an atrium, a garage, a stage, or hazardous materials, then check that the extra features it brings appear in every discipline’s drawings and in the specifications. AI can flag conflicts; the design team and the building official decide which requirements apply.
What does IBC Chapter 4 cover?
Chapter 4 of the 2024 IBC, Special Detailed Requirements Based on Occupancy and Use, applies to the occupancies and uses it describes in addition to the code’s general occupancy and construction requirements. Its sections include covered and open mall buildings (402), high-rise buildings (403), atriums (404), underground buildings (405), motor-vehicle-related occupancies (406), Group I-2 (407), Group I-3 (408), motion picture projection rooms (409), stages, platforms, and technical production areas (410), special amusement areas (411), aircraft-related occupancies (412), combustible storage (413), hazardous materials (414), Groups H-1 to H-5 (415), spray application of flammable finishes (416), Groups I-1, R-1, R-2, R-3, and R-4 (420), hydrogen fuel gas rooms (421), ambulatory care facilities (422), storm shelters (423), medical gas systems (427), and higher education laboratories (428).
Chapter 4, Special Detailed Requirements Based on Occupancy and Use, on ICC Digital Codes is part of the 2024 IBC. ICC’s store still lists the 2027 IBC as a pre-order due in mid-October, and the 2027 edition was not on Digital Codes. Both checked October 7, 2026. Section numbers and titles below are from the 2024 edition; they can move between editions, and states and cities adopt a specific edition with amendments. Record the edition the jurisdiction enforces before citing a section.
This guide follows one chapter. The IBC guide covers the code analysis as a whole, and state codes built on the IBC, such as the California Building Code, may renumber or amend the chapter. A Chapter 4 condition starts from the classification in Chapter 3. Many sections point to systems in the Chapter 9 guide and to NFPA standards that have their own guides.
Gather the code analysis and the sheets the condition reaches
Collect the code analysis and its list of special conditions, the life safety plans, the architectural plans and sections, the fire protection and fire alarm drawings, the mechanical smoke control drawings and narrative, the electrical emergency and standby power drawings, the hazardous materials inventory where one applies, and the specification sections for the systems involved.
A special condition is often named once, on the code sheet. Upload every discipline so the features it brings can be traced from that one line.
Follow each special condition through every discipline
| Review question | Sources to compare | Decision to record |
|---|---|---|
| Conditions identified | Code analysis, building sections, floor plans | Confirm the documents agree on which Chapter 4 conditions apply, such as height, atrium, or garage. |
| High-rise features | Fire alarm, sprinkler, electrical, and architectural drawings | Check that the features the code analysis lists for a high-rise appear in each discipline. |
| Atriums and smoke control | Sections, smoke control narrative, mechanical and alarm drawings | Match the atrium boundaries and smoke control approach across documents. |
| Garages and vehicle areas | Garage plans, ventilation drawings, sprinkler notes | Confirm the garage classification and the ventilation and protection it relies on agree. |
| Stages and assembly features | Stage plans, sections, fire protection drawings | Identify stage or production areas whose protection differs between sheets. |
| Hazardous materials | Inventory, room plans, rated wall plans, specifications | Ask the designer to confirm control areas or rooms shown for the quantities listed. |
Smoke control follows the NFPA 92 guide, parking garages the NFPA 88A guide, aircraft hangars the NFPA 409 guide, and hazardous materials the NFPA 400 guide. Emergency and standby power for high-rise systems follows the NFPA 110 guide.
Example: the atrium is drawn but its smoke control is not
Hypothetical example. A building section shows a multistory open space connecting three floors, and the code analysis lists an atrium. The mechanical drawings show no smoke control fans or dampers for it, and the fire alarm drawings show no detection or control interface for the space.
The code analysis and building sections show an atrium connecting three floors, while the mechanical and fire alarm drawings show no smoke control equipment or interface for it. Please confirm the approach for the atrium and coordinate the mechanical, fire alarm, and architectural documents.
The architect and the fire protection engineer confirm the atrium approach, then the mechanical and fire alarm designers add or explain the system. The building official decides compliance.
Review special occupancy conditions with Groundbook
Upload the current drawings and specifications to Groundbook, and state the edition, amendments, and review scope in your instructions. Add the IBC Chapter 4 edition the project uses from a copy you are licensed to use, where the license permits uploading it, and the jurisdiction’s published amendments. See how Groundbook works with local and licensed codes.
Compare the code analysis and its special conditions with the life safety plans, architectural plans and sections, fire protection and fire alarm drawings, smoke control narrative and mechanical drawings, electrical emergency power drawings, hazardous materials inventory, and specifications. Flag conditions such as a high-rise, atrium, garage, stage, or hazardous materials area that one discipline shows and another omits. Use the supplied IBC edition and local amendments and cite both sources.
Groundbook links each potential finding to the sheets involved and the code section you uploaded.
Document review does not decide which Chapter 4 requirements apply, design smoke control, or replace the design team, the fire protection engineer, or the building official.