Take the construction type stated in the code analysis, then check that the structural members, floor and roof assemblies, exterior and interior walls, fireproofing, and specified materials all match it, including any combustible materials allowed in noncombustible types. AI can flag conflicts; the architect, the structural engineer, and the building official decide compliance.
What does IBC Chapter 6 cover?
Chapter 6 of the 2024 IBC, Types of Construction, governs how buildings are classified by type of construction. It has three sections: general provisions with the table of fire-resistance rating requirements for building elements (601), construction classification (602), and combustible material in Types I and II construction (603). Section 602 names five types: Types I and II, whose building elements are noncombustible except as the code allows; Type III, with noncombustible exterior walls; Type IV, with mass timber or noncombustible elements, subdivided into IV-A, IV-B, IV-C, and IV-HT; and Type V, where elements may be any material the code permits.
Chapter 6, Types of Construction, 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. The type works with the occupancy in Chapter 3 and the limits in Chapter 5, and the rated elements it requires are built under the Chapter 7 guide.
Gather the code analysis and every material decision
Collect the code analysis with the construction type, the structural drawings and general notes, the wall, floor, and roof assembly types with their listings, building sections, exterior wall sections and details, the fireproofing plans or schedule, and the specification sections for structural materials, sheathing, framing, roofing, cladding, and fireproofing.
A change of structural system late in design, such as wood framing on a podium or exposed mass timber, often reaches the structural drawings before the code analysis. Upload both together.
Check every element against the stated type
| Review question | Sources to compare | Decision to record |
|---|---|---|
| Type stated | Code analysis, cover sheet, structural notes | Confirm one construction type across documents, and the type of each building if there are fire walls. |
| Structural members | Structural drawings, fireproofing schedule, details | Check columns, beams, and bearing walls have the material and protection the type requires. |
| Floor and roof assemblies | Assembly types, sections, structural framing plans | Match each floor and roof assembly to the type and its rating. |
| Exterior walls | Wall sections, elevations, specifications | Find exterior wall materials that differ from what the stated type allows. |
| Combustible materials | Specifications, interior finish plans, blocking and trim details | Ask the designer to confirm the basis for combustible materials in Type I or II construction. |
| Mass timber | Structural drawings, exposed timber details, specifications | Confirm the Type IV subdivision and any protection shown agree between sheets. |
Structural steel follows the AISC 360 guide, concrete the ACI 318 guide, and wood the NDS guide. Exterior wall materials continue in the IBC Chapter 14 guide, and the structural drawing checklist is the working log.
Example: wood blocking in a noncombustible building
Hypothetical example. The code analysis states a noncombustible construction type. The exterior wall sections show wood blocking and wood sheathing behind the cladding, and the specification section for rough carpentry lists untreated lumber with no mention of an allowance.
The code analysis states a noncombustible construction type, while the exterior wall sections show wood blocking and sheathing and the rough carpentry section lists untreated lumber. Please confirm the basis for the combustible materials or coordinate the wall details and specifications with the stated type.
The architect confirms whether the materials fall within an allowance for the type or changes them. The building official decides compliance.
Review construction type 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 6 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 construction type in the code analysis with the structural drawings and notes, assembly types, building and wall sections, fireproofing schedule, and the structural, framing, sheathing, cladding, and fireproofing specifications. Flag elements whose material or protection differs from the stated type, combustible materials without a stated basis, and buildings or parts of buildings where the type differs between documents. Use the supplied IBC edition and local amendments and cite both sources.
Groundbook links each potential finding to the sheets, specification articles, and the code section you uploaded.
Document review does not choose a construction type, rate assemblies, or replace the architect, the structural engineer, or the building official.