Appendix A — GUIDELINES FOR THE SEISMIC RETROFIT OF EXISTING BUILDINGS
A303 Structural Weaknesses — 2025 California Existing Building Code
California Existing Building Code (Title 24, Part 10) · 2025 edition · updated 2026-10-19 · California
CBSC: official editions, supplements and errata
Italicized text is a California amendment to the model code, as printed in the official publication.
Cite as: 2025 California Existing Building Code (Title 24, Part 10) § A303 · Effective January 1, 2026 · Official source: Building Standards Commission
A303.1 General.¶
[BS] A303.1 General. For the purposes of this chapter, any of the following conditions shall be deemed a structural weakness:
- Sill plates or floor framing that are supported directly on the ground without a foundation system that conforms to the building code.
- A perimeter foundation system that is constructed only of wood posts supported on isolated pad footings.
- Perimeter foundation systems that are not continuous.
Exceptions:
- Existing single-story exterior walls not exceeding 10 feet (3048 mm) in length, forming an extension of floor area beyond the line of an existing continuous perimeter foundation.
- Porches, storage rooms and similar spaces not containing fuel-burning appliances.
- A perimeter foundation system that is constructed of unreinforced masonry or stone.
- Sill plates that are not connected to the foundation or that are connected with less than what is required by the building code.
Exception: Where approved by the code official, connections of a sill plate to the foundation made with other than sill bolts shall be accepted if the capacity of the connection is equivalent to that required by the building code. 6. Cripple walls that are not braced in accordance with the requirements of Section A304.4 and Table A304.3.1, or cripple walls not braced with diagonal sheathing or wood structural panels in accordance with the building code.
Continue researching
Related topics
State and federal sources. Edit the document title or filters, then run your search.
Get a plain-English answer with a citation back to this text.
Ask AI about this code