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In the errata issued on July 25, 2024, footnote l was removed; however, there does not appear to be any explanation in the commentary clarifying the reason for disallowing OCCs. In ASCE 7-16, OCCs were permitted for buildings per Section 12.2.5.6.2, with limitations tied to roof dead load. The commentary referenced limits on individual column axial load, but this did not appear to constitute a prohibition of OCC systems.

Additionally, Table 15.4-1 in ASCE 7-22 still permits Steel Ordinary Moment Frames in SDC D, E, and F, subject to certain limitations. Section 15.4.1 also allows the use of either Table 12.2-1 or Table 15.4-1 for nonbuilding structures similar to buildings. This appears to create a potential inconsistency between the two tables.

Historically, OCCs have been widely used in the industry for structures such as carport canopies, shade structures, and similar applications. Many of these structures are not governed by seismic design. Disallowing OCCs lead to additional requirements per AISC 341-22, including higher ductility demands, protected zone requirements, and more stringent connection detailing, which doesn't make sense since wind load is governing the design. 

#ASCE7-22

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Errata are intended to correct editorial issues with the standard, but not to make technical change.  Reasons are never posted for errata.  Ordinary concrete cantilever columns have never been permitted in Seismic Design Category C, D, E or F for building structures.  The section 12.5. limitation on axial loads was always an additional limitation to the requirements of Table 12.2-1, not an expansion to other Seismic Design Categories.

Some structural systems not permitted for buildings are permitted for nonbuilding structures, typically with much lower R factors, in recognition of the historic acceptable performance of nonbuilding structures, the lower occupancy associated with such structures, and because such structures are often massive for reasons other than seismic resistance and can be practically designed to such low R factors.

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Ronald Hamburger, SE
Consulting Principal
Simpson Gumpertz & Heger
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This message was posted by a user wishing to remain anonymous

Ronald, 

Thank you for your message.

I was referring to Steel Ordinary Cantilevered Column. Steel OCC was permitted under ASCE 7-16 Table 12.2-1 footnote l. In ASCE 7-22, the footnote l applied to OCC but was removed in the errata issued on July 25, 2024. That causes a conflict between table 15.4-1 and Table 12.2-1. Table 15.4-1 allows Steel Ordinary moment frames in SDC D,E,F with R =1, which is similar to OCC. Some building officials has required to follow Table 12.2-1 for Seismic Coefficients for Nonbuilding Structures Similar to Buildings which doesn't allow OCC.

For example, for a bleacher shade cover with fabric roof, If we follow Table 15.4-1 using R=1, we can go no limit for SDC D - F. But if we follow Table 12.2-1, is Ordinary Cantilevered System allowed in SDC D -F for this case? 

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Original Message:
Sent: 05-13-2026 10:05 AM
From: Ronald Hamburger
Subject: ASCE 7-22 Ordinary Cantilevered Columns in SDC D E F

Errata are intended to correct editorial issues with the standard, but not to make technical change.  Reasons are never posted for errata.  Ordinary concrete cantilever columns have never been permitted in Seismic Design Category C, D, E or F for building structures.  The section 12.5. limitation on axial loads was always an additional limitation to the requirements of Table 12.2-1, not an expansion to other Seismic Design Categories.

Some structural systems not permitted for buildings are permitted for nonbuilding structures, typically with much lower R factors, in recognition of the historic acceptable performance of nonbuilding structures, the lower occupancy associated with such structures, and because such structures are often massive for reasons other than seismic resistance and can be practically designed to such low R factors.

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Ronald Hamburger, SE
Consulting Principal
Simpson Gumpertz & Heger
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The ASCE 7-22 committee felt that 1) having 3 different types of steel cantilever column system (OMF, IMF, SMF) was both confusing and inappropriate.  Given that all cantilever column systems resist inelastic demand by hinging at the base, the committee felt that the compactness requirements required of SMF systems was merited.  As indicated in the previous response, the committee is more tolerant of some systems in non-building structure use do to the reduced risk to life, and other factors.

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Ronald Hamburger, SE
Consulting Principal
Simpson Gumpertz & Heger
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Original Message:
Sent: 05-20-2026 01:37 PM
From: Anonymous Member
Subject: ASCE 7-22 Ordinary Cantilevered Columns in SDC D E F

This message was posted by a user wishing to remain anonymous

Ronald, 

Thank you for your message.

I was referring to Steel Ordinary Cantilevered Column. Steel OCC was permitted under ASCE 7-16 Table 12.2-1 footnote l. In ASCE 7-22, the footnote l applied to OCC but was removed in the errata issued on July 25, 2024. That causes a conflict between table 15.4-1 and Table 12.2-1. Table 15.4-1 allows Steel Ordinary moment frames in SDC D,E,F with R =1, which is similar to OCC. Some building officials has required to follow Table 12.2-1 for Seismic Coefficients for Nonbuilding Structures Similar to Buildings which doesn't allow OCC.

For example, for a bleacher shade cover with fabric roof, If we follow Table 15.4-1 using R=1, we can go no limit for SDC D - F. But if we follow Table 12.2-1, is Ordinary Cantilevered System allowed in SDC D -F for this case?