CBC · California Building Code
Glass unit and adobe masonry: special provisions
Glass‑block walls must be framed and designed so the frame — not the glass units — resists loads and seismic forces; glass block is generally not allowed in load‑bearing or fire‑resistance‑rated walls unless a limited exception (with a listed 3/4‑hour assembly) applies. Adobe (clay) plaster and walls have specific material, test and finish requirements (including a prohibition on Portland‑cement finish over clay plaster) and, for some projects, agency limitations on empirical adobe design.
Last reviewed: July 5, 2026
What the code requires — 2-4 sentences
Glass‑unit (glass‑block) masonry must be built to the rules in the CBC and TMS 402: it must be designed for seismic forces and you may not rely on the glass block itself to carry stresses (see § 2110.1). Solid or hollow glass block is not permitted for load‑bearing work or in fire walls/party walls/fire barriers/fire partitions or smoke barriers except where narrowly allowed by the listed exceptions (§ 2110.1.1). Empirical adobe masonry provisions are covered in § 2109; the CBC contains specific material and finish rules for clay (adobe) plaster (see § 2109.2.4.8.9 and related subsections).
Requirements in detail
Glass‑unit masonry (controls and limits)
- Design standard: Glass unit masonry shall comply with Chapter 14 of TMS 402 and the CBC provisions in § 2110.1. Glass‑block walls or panels shall be designed for seismic forces and stresses in glass block shall not be utilized (i.e., the structural system — frame, reinforcement, anchors — must carry the actions). § 2110.1.
- Prohibited uses: Solid or hollow approved glass block shall not be used in fire walls, party walls, fire barriers, fire partitions or smoke barriers, or for load‑bearing construction, except as permitted by the specific exceptions in § 2110.1.1. § 2110.1.1.
- Construction framing and attachment: Glass block assemblies are to be erected with mortar and reinforcement in metal channel‑type frames, structural frames, masonry or concrete recesses or embedded panel anchors, or other approved joint materials. Wood strip framing is not permitted in walls that are required to have a fire‑resistance rating. § 2110.1.1.
- Special inspection/quality assurance: Where applicable by risk category, special inspection and testing requirements referenced in Chapter 17 apply to glass unit masonry (see § 1705 and TMS 602 references for Risk Categories II–IV and for Risk Category IV Level 2). § 1705.4 / § 1705.4.1.
Adobe (empirical adobe masonry) — material & finish controls
- Scope/approval: Empirical design provisions for adobe masonry are contained in § 2109 (Chapter 21). Some state agencies (OSHPD and DSA) identify limitations on the use of empirical adobe design; the CBC notes these agencies' non‑adoption for certain applications. § 2109 (heading).
- Clay plaster definitions and tests: Clay plaster is defined and must meet the clay/soil binder requirements; suitability of clay subsoil is to be determined by ribbon and ball tests per ASTM E2392/E2392M appendix figures (the CBC references these tests in § 2109.2.4.8.9.2). § 2109.2.4.8.9.1–.2.
- Weather exposure and finish limitations: Clay plaster exposed to direct or wind‑driven rain or snow must be finished with an approved erosion‑resistant finish; clay plaster is not permitted on weather‑exposed parapets. Portland‑cement containing plaster is not permitted as a finish coat over clay plaster. § 2109.2.4.8.9.3–.4.
- Lathing exception: For unstabilized adobe walls finished with unstabilized clay plaster, lathing is not required (i.e., code recognizes a permissive exception). § 2109.2.4.8.9.5.
- Lintels and other structural members: Lintels are treated as structural members and must be designed per Chapter 16 provisions; see § 2109.2.4.9 for the reference to lintel design. § 2109.2.4.9.
Decision‑relevant dimensions / values (quick reference)
| Topic | Decision value / limit | Code reference |
|---|---|---|
| Must design glass block walls for seismic forces | Yes — do not use glass block stresses | § 2110.1 — |
| Glass block in fire/resistance‑rated walls | Prohibited in fire walls/party walls/fire barriers/fire partitions/smoke barriers and for load‑bearing construction except listed exceptions | § 2110.1.1 — |
| Fire‑protection rating threshold for allowed opening protective use | Glass‑block assemblies having fire protection rating of not less than 3/4 hour permitted as opening protectives in certain 1‑hour barriers/partitions | Exception to § 2110.1.1 — |
| Framing/attachment for glass unit masonry | Must use metal channel frames, structural frames, masonry/concrete recesses, embedded anchors or approved joint materials; no wood strip in rated walls | § 2110.1.1 — |
| Clay plaster over adobe exposed to weather | Must have approved erosion‑resistant finish; clay plaster prohibited on exposed parapets | § 2109.2.4.8.9.3 — |
| Finish coat over clay plaster | Portland cement–containing plaster not permitted as finish over clay plaster | § 2109.2.4.8.9.4 — |
| Lathing for unstabilized adobe with unstabilized clay plaster | Lathing not required | § 2109.2.4.8.9.5 — |
| Special inspection for glass unit masonry | TMS 602 / Chapter 17 special inspection requirements apply for certain Risk Categories (see § 1705) | § 1705.4.1 and related TMS 602 references — |
Note on unavailable text: some § 2109 subsections (for example § 2109.2.4.5, “Foundations, adobe”) are identified in the CBC index but the detailed text for that specific subsection was not included in the retrieved excerpts I was provided; therefore foundation dimensions/requirements from that subsection are not quoted here.
How the glass‑block rule works in practice (mechanics)
- You must treat glass‑block construction as a framed panel or veneer system: the frame, anchor system and reinforcement carry structural and seismic forces, not the glass units. § 2110.1.
- Where a fire‑resistance rating is required, you may not substitute wood strip framing or rely on untested glass block assemblies — consult the exception language and Section 716 for opening protectives if proposing glass‑block as an opening protective. § 2110.1.1 and Exception 1; see also § 716.
Exceptions & special cases
- Fire‑protective opening use: Glass‑block assemblies with a fire protection rating of at least 3/4 hour are permitted as opening protectives in fire barriers/fire partitions/smoke barriers that require a 1‑hour rating or less and do not enclose exit stairways, ramps or exit passageways (Exception to § 2110.1.1).
- Special inspections: Glass unit masonry used in buildings of higher Risk Categories is subject to the CBC special inspection program and quality assurance levels per TMS 602 and § 1705 (special inspection levels and tables are cross‑referenced). § 1705.4.1 and related TMS 602 references.
- Agency limitations on adobe empirical design: The CBC notes that OSHPD and DSA do not permit empirical adobe design for their projects — check agency requirements for projects under those jurisdictions. § 2109 heading / notes.
Common mistakes
- Relying on glass block strength: treating glass units as structural members or using block stresses for design — prohibited by § 2110.1.
- Using wood strip framing where fire‑resistance is required: wood strip framing is not permitted in walls required to have a fire‑resistance rating (§ 2110.1.1).
- Assuming special inspections never apply: for higher Risk Category structures, glass unit masonry does trigger TMS 602/Chapter 17 special inspection requirements (§ 1705.4.1).
- Applying cement‑based finish over clay plaster: the CBC forbids Portland‑cement finishes over clay plaster (§ 2109.2.4.8.9.4).
- Forgetting required tests for clay subsoils: the code requires specific ribbon/ball tests for clay suitability per ASTM E2392/E2392M references (§ 2109.2.4.8.9.2).
Worked example — concrete scenario
Scenario: A designer proposes a 7 ft high by 4 ft wide interior glass‑block panel in a non‑loadbearing corridor wall of a three‑story office building (Risk Category II). The wall is within a fire partition that has a required 1‑hour fire resistance.
Steps to apply the CBC:
- Confirm applicability of § 2110.1: glass unit masonry must be designed per TMS 402 Chapter 14 and for seismic forces; you may not use stresses in the glass block. The design must therefore specify a frame and reinforcement sized to carry lateral and vertical actions; do not rely on glass block compressive/tensile strength. § 2110.1.
- Fire‑rating check against § 2110.1.1 and its Exception 1: because the partition requires a 1‑hour rating, an opening protective of glass block is allowed only if the glass‑block assembly has a fire protection rating of not less than 3/4 hour and the assembly complies with Section 716. If the proposed glass assembly is not tested/listed for ≥3/4 hour, it cannot be used as the opening protective in that partition. § 2110.1.1 (Exception 1).
- Framing and attachment: specify a metal channel or structural frame with anchors or embedded panel anchors; specify mortar/reinforcement details (per TMS 402) so the frame/resistive elements, not the glass, resist seismic forces. § 2110.1.1 and § 2110.1.
- Special inspection: for Risk Category II, glass unit masonry designed under § 2110 is subject to the periodic special inspection requirements in TMS 602 and Chapter 17 (see § 1705.4.1 and the TMS 602 cross‑references). Include the required quality assurance level in the construction documents. § 1705.4.1.
Result: The panel may be used only if (a) the glass‑block assembly is framed so the frame carries structural/seismic loads; (b) if the panel is intended as an opening protective in a 1‑hour partition, the assembly is tested/listed for ≥3/4 hour per Exception 1 to § 2110.1.1 and Section 716; and (c) the project includes the required special inspection program called out by § 1705 (per TMS 602) for Risk Category II glass unit masonry.
Related provisions
- Special inspections and quality assurance — § 1705 (and § 1705.4.1 with TMS 602 references).
- Opening protectives — § 716 (used by Exception 1 in § 2110.1.1).
- Masonry materials and construction details — Chapter 21 / § 2103 et seq. (general masonry materials and construction).
- Adobe plaster tests and definitions — § 2109.2.4.8.9.1–.5.
- Lintel design (structural members) — § 2109.2.4.9 (referencing Chapter 16 design rules).
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
CBC § 6.1.7.3.1 High relevance — show source text
6.1.7.3.1 – Welded splices shall not be permitted in plastic hinge zones of intermediate or special reinforced walls.
6.1.7.2.1 – Mechanical splices shall be classified as Type 1 or 2 in accordance with Section 18.2.7.1 of ACI 318. Type 1 mechanical splices shall not be used within a plastic hinge zone or within a beam-column joint of intermediate or special reinforced masonry shear walls. Type 2 mechanical splices are permitted in any location within a member.
SECTION 2109 A —EMPIRICAL DESIGN OF ADOBE MASONRY
Not permitted by OSHPD and DSA.
SECTION 2110 A —GLASS UNIT MASONRY
2110 A .1 General. Glass unit masonry construction shall comply with Chapter 14 of TMS 402 and this section.
Masonry glass block walls or panels shall be designed for seismic forces. Stresses in glass block shall not be utilized.
2110 A .1.1 Limitations. Solid or hollow approved glass block shall not be used in fire walls, party walls, fire barriers, fire partitions or smoke barriers, or for load-bearing construction. Such blocks shall be erected with mortar and reinforcement in metal channeltype frames, structural frames, masonry or concrete recesses, embedded panel anchors as provided for both exterior and interior walls or other approved joint materials. Wood strip framing shall not be used in walls required to have a fire-resistance rating by other provisions of this code.
Exceptions:
- Glass-block assemblies having a fire protection rating of not less than [3] / 4 hour shall be permitted as opening protectives in accordance with Section 716 in fire barriers, fire partitions and smoke barriers that have a required fireresistance rating of 1 hour or less and do not enclose exit stairways and ramps or exit passageways.
- Glass-block assemblies as permitted in Section 404.6, Exception 2.
SECTION 2111 A —MASONRY FIREPLACES
2111 A .1 General. The construction of masonry fireplaces, consisting of concrete or masonry, shall be in accordance with this section.
2111 A .2 Fireplace drawings. The construction documents shall describe in sufficient detail the location, size and construction of masonry fireplaces. The thickness and characteristics of materials and the clearances from walls, partitions and ceilings shall be indicated.
2111 A .3 Footings and foundations. Footings for masonry fireplaces and their chimneys shall be constructed of concrete or solid masonry not less than 12 inches (305 mm) thick and shall extend not less than 6 inches (153 mm) beyond the face of the fireplace or
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foundation wall on all sides. Footings shall be founded on natural undisturbed earth or engineered fill below frost depth. In areas not subjected to freezing, footings shall be not less than 12 inches (305 mm) below finished grade.
CBC § 8.3.4.4.3 High relevance — show source text
Cantilevered walls not part of a building and not carrying applied vertical loads need not meet these minimum requirements but their design must comply with stress and over-_
turning requirements.|�
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8.3.4.4.3 Every pier or wall section with a width less than three times its thickness shall be designed and constructed as required for columns if such pier is a structural member. Every pier or wall section with a width between three and five times its thickness or less than one half the height of adjacent openings shall have all horizontal steel in the form of ties except that in walls 12 inches (305 mm) or less in thickness such steel may be in the form of hair-pins.
SECTION 2108 A —STRENGTH DESIGN OF MASONRY
2108 A .1 General. The design of masonry structures using strength design shall comply with Section 2106 and the requirements of Chapters 1 through 7 and Chapter 9 of TMS 402, except as modified by Sections 2108 A .2 through 2108 A .3.
2108 A .2 TMS 402, Section 6.1.6, development. Add a second paragraph to Section 6.1.6 as follows:
The required development length of reinforcement need not be greater than 72 d b .
2108 A .3 TMS 402, Section 6.1.6.1.1, splices. Add to Sections 6.1.7.2.1 and 6.1.7.3.1 as follows:
6.1.7.3.1 – Welded splices shall not be permitted in plastic hinge zones of intermediate or special reinforced walls.
6.1.7.2.1 – Mechanical splices shall be classified as Type 1 or 2 in accordance with Section 18.2.7.1 of ACI 318. Type 1 mechanical splices shall not be used within a plastic hinge zone or within a beam-column joint of intermediate or special reinforced masonry shear walls. Type 2 mechanical splices are permitted in any location within a member.
SECTION 2109 A —EMPIRICAL DESIGN OF ADOBE MASONRY
Not permitted by OSHPD and DSA.
SECTION 2110 A —GLASS UNIT MASONRY
2110 A .1 General. Glass unit masonry construction shall comply with Chapter 14 of TMS 402 and this section.
Masonry glass block walls or panels shall be designed for seismic forces. Stresses in glass block shall not be utilized.
2110 A .1.1 Limitations. Solid or hollow approved glass block shall not be used in fire walls, party walls, fire barriers, fire partitions or smoke barriers, or for load-bearing construction. Such blocks shall be erected with mortar and reinforcement in metal channeltype frames, structural frames, masonry or concrete recesses, embedded panel anchors as provided for both exterior and interior walls or other approved joint materials. Wood strip framing shall not be used in walls required to have a fire-resistance rating by other provisions of this code.
CBC § 3106.3 High relevance — show source text
Roof construction 3106.3 Masonry Chapter 21A Adhered veneer 1404.11
Adobe 2109 Anchorage 1604.8.2 Anchored veneer 1404.7
Architectural cast stone 2103.1
Calculated fire resistance 722.4 Chimneys 2113 Construction 2104 Dampproofing 1805.2.2 Design, methods 2101.2, 2107, 2108, 2109
Fire resistance, calculated 722.3.2,
722.3.4
Fireplaces 2111 Floor anchorage 1604.8.2 Foundation walls 1807.1.5
Foundations, adobe 2109.2.4.5 Glass unit 2110
Heaters 2112
Inspection, special 1705.4 Joint reinforcement 2103.4
Materials 603.1, 2103 Penetrations 714 Quality assurance 2105 Rodentproofing Appendix F Roof anchorage 1604.8.1 Seismic provisions 2106 Serviceability 1604.3.4 Supported by wood 2104.1.1, 2304.13 Surface bonding 2103.2.2 Veneer 1404.11, 1404.7, 2101.2.1,
2308.10.10 Wall anchorage 1604.8.2 Waterproofing 1805.3.2 Mass Notification Systems 917 Mass Timber 508, 509, 602, 703, 718, 722 Materials
Alternates 104.2.3
Aluminum Chapter 20 Concrete Chapter 19, Chapter 19A Glass and glazing Chapter 24 Gypsum Chapter 25 Masonry Chapter 21, Chapter 21A Noncombustible 703.4
Plastic Chapter 26 Steel Chapter 22, Chapter 22A Testing (see Testing) 1707 Wood Chapter 23 Materials and Construction Methods for Exterior Exposure Chapter 7A Means of Appeals 113, Appendix B Means of Egress Chapter 10, 202 Accessible 1009, 2702.2 Aircraft related 412.2.2, 412.2.5.1, 412.4.2, 412.6.1, 412.7.3 Alternating tread device 412.7.3, 1006.2.2.1, 1006.2.2.2, 1011.14 Ambulatory care facilities 422.3.1, 422.3.3 Assembly 1009.1, 1030 Atrium 404.9, 404.11, 707.3.6 Capacity 1005.3
Laboratories
Classification of 304.1, 307.1.1 Hazardous materials 414, 415 Higher education laboratories 304.4, 428 Incidental uses Table 509.1
Ladders
Boiler, incinerator and furnace
rooms 1006.2.2.1
Construction 1011.15, 1011.16, 1014.2, 1014.7, 1015.3, 1015.4 Emergency escape window wells 1031.5.2
CBC § 1705.4.1 High relevance — show source text
1705.4.1 Glass unit masonry and masonry veneer in Risk Category IV. Special inspections and tests for glass unit masonry or masonry veneer designed in accordance with Section 2110 or Chapter 14, respectively, where they are part of a structure classified as Risk Category IV shall be performed in accordance with TMS 602 Level 2. [OSHPD 1R, 2 & 5] Not permitted by OSHPD.
[OSHPD 1R, 2 & 5] Glass unit masonry and masonry veneer in Risk Category II, III or IV. Special inspections and tests for glass unit masonry or masonry veneer designed by Section 2110 or Chapter 14, respectively, in structures classified as Risk Category II, III or IV, shall be performed in accordance with TMS 602 Tables 3 and 4, Level 2 Quality Assurance.
1705.4.1.1 TMS 602 Section 1.6 Quality Assurance. [OSHPD 1R, 2 & 5] Replace footnote (d) as follows: (d) Periodic special inspection is required for all veneer.
1705.4.2 Vertical masonry foundation elements. Special inspections and tests of vertical masonry foundation elements shall be performed in accordance with Section 1705.4.
1705.5 Wood construction. Special inspections of prefabricated wood structural elements and assemblies shall be in accordance with Section 1704.2.5. Special inspections of site-built assemblies shall be in accordance with this section.
1705.5.1 High-load diaphragms. High-load diaphragms designed in accordance with Section 2306.2 shall be installed with special inspections as indicated in Section 1704.2. The special inspector shall inspect the wood structural panel sheathing to ascertain whether it is of the grade and thickness shown on the approved construction documents. Additionally, the special inspector must verify the nominal size of framing members at adjoining panel edges, the nail or staple diameter and length, the number of fastener lines and that the spacing between fasteners in each line and at edge margins agrees with the approved construction documents.
1705.5.2 Metal-plate-connected wood trusses spanning 60 feet or greater. Where a truss clear span is 60 feet (18 288 mm) or greater, the special inspector shall verify that the temporary installation restraint/bracing and the permanent individual truss member restraint/bracing are installed in accordance with the approved truss submittal package.
1705.5.3 Mass timber construction. Special inspections of mass timber elements in Types IV-A, IV-B and IV-C construction shall be in accordance with Table 1705.5.3.
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SPECIAL INSPECTIONS AND TESTS
TABLE 1705.5.3—REQUIRED SPECIAL INSPECTIONS OF MASS TIMBER CONSTRUCTION Col2 Col3 Col4 Col5 TYPE TYPE TYPE CONTINUOUS
SPECIAL INSPECTIONPERIODIC SPECIAL
INSPECTION1. Inspection of anchorage and connections of mass timber construction to timber deep
foundation systems.CBC § 2109.2.4.8.9.3 High relevance — show source text
2109.2.4.8.9.3 Weather-exposed locations. Clay plaster exposed to water from direct or wind-driven rain or snow shall be finished with an approved erosion-resistant finish. The use of clay plasters shall not be permitted on weather-exposed parapets.
2109.2.4.8.9.4 Prohibited finish coat. Plaster containing Portland cement shall not be permitted as a finish over clay plaster.
2109.2.4.8.9.5 Conditions where lathing is not required. For unstabilized adobe walls finished with unstabilized clay plaster, lathing shall not be required.
2109.2.4.9 Lintels. Lintels shall be considered to be structural members and shall be designed in accordance with the applicable provisions of Chapter 16.
SECTION 2110—GLASS UNIT MASONRY
2110.1 General. [OSHPD 1R, 2 & 5] Masonry glass block walls or panels shall be designed for seismic forces. Stresses in glass block shall not be utilized. Glass unit masonry construction shall comply with Chapter 14 of TMS 402 and this section.
2110.1.1 Limitations. Solid or hollow approved glass block shall not be used in fire walls, party walls, fire barriers, fire partitions or smoke barriers, or for load-bearing construction. Such blocks shall be erected with mortar and reinforcement in metal channeltype frames, structural frames, masonry or concrete recesses, embedded panel anchors as provided for both exterior and interior walls or other approved joint materials. Wood strip framing shall not be used in walls required to have a fire-resistance rating by other provisions of this code.
Exceptions:
- Glass-block assemblies having a fire protection rating of not less than [3] / 4 hour shall be permitted as opening protectives in accordance with Section 716 in fire barriers, fire partitions and smoke barriers that have a required fireresistance rating of 1 hour or less and do not enclose exit stairways and ramps or exit passageways.
- Glass-block assemblies as permitted in Section 404.6, Exception 2.
SECTION 2111—MASONRY FIREPLACES
2111.1 General. The construction of masonry fireplaces, consisting of concrete or masonry, shall be in accordance with this section.
2111.2 Fireplace drawings. The construction documents shall describe in sufficient detail the location, size and construction of masonry fireplaces. The thickness and characteristics of materials and the clearances from walls, partitions and ceilings shall be indicated.
2111.3 Footings and foundations. Footings for masonry fireplaces and their chimneys shall be constructed of concrete or solid masonry not less than 12 inches (305 mm) thick and shall extend not less than 6 inches (153 mm) beyond the face of the fireplace or foundation wall on all sides. Footings shall be founded on natural undisturbed earth or engineered fill below frost depth. In areas not subjected to freezing, footings shall be not less than 12 inches (305 mm) below finished grade.
2111.3.1 Ash dump cleanout. Cleanout openings, located within foundation walls below fireboxes, where provided, shall be equipped with ferrous metal or masonry doors and frames constructed to remain tightly closed, except when in use. Cleanouts shall be accessible and located so that ash removal will not create a hazard to combustible materials.
CBC § 802.3 High relevance — show source text
Decorative materials 419, 802.3, 806 Floor finish 804, 805 Foam plastic insulation 2603.3, 2603.4 Foam plastic trim 806.6.1, 2604.2 Insulation 807 Light-transmitting plastics 2606 Signs 402.6.4, 2611 Site-fabricated stretch systems 803.10 Trim 806.6, 806.7 Wall and ceiling finishes 803 Wet location 1210 Intermodal Shipping Container 3114 Interpretation, Code 104.1
Jails [see Institutional (see Group I-3)] 308.5, 408 Joint Gypsum board 2508.5 Lumber sheathing 2308.11.10 Waterproofing 1805.3.3 Joints, Fire-resistant Systems 715 Special inspection 1705.18
Kiosks 402.6.2
Kitchens 303.3, 306.2 Accessibility 1133A, 11B-212 Dimensions 1209 Means of egress 1016.2 Occupant load Table 1004.5 Sinks Chapter 29
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INDEX
Marquees 3106, H113 Construction 3106.5
Drainage, water 3201.4 Live load Table 1607.1, 1607.14 Prohibited location 3106.4
Roof construction 3106.3 Masonry Chapter 21A Adhered veneer 1404.11
Adobe 2109 Anchorage 1604.8.2 Anchored veneer 1404.7
Architectural cast stone 2103.1
Calculated fire resistance 722.4 Chimneys 2113 Construction 2104 Dampproofing 1805.2.2 Design, methods 2101.2, 2107, 2108, 2109
Fire resistance, calculated 722.3.2,
722.3.4
Fireplaces 2111 Floor anchorage 1604.8.2 Foundation walls 1807.1.5
Foundations, adobe 2109.2.4.5 Glass unit 2110
Heaters 2112
Inspection, special 1705.4 Joint reinforcement 2103.4
Materials 603.1, 2103 Penetrations 714 Quality assurance 2105 Rodentproofing Appendix F Roof anchorage 1604.8.1 Seismic provisions 2106 Serviceability 1604.3.4 Supported by wood 2104.1.1, 2304.13 Surface bonding 2103.2.2 Veneer 1404.11, 1404.7, 2101.2.1,
2308.10.10 Wall anchorage 1604.8.2 Waterproofing 1805.3.2 Mass Notification Systems 917 Mass Timber 508, 509, 602, 703, 718, 722 Materials
Alternates 104.2.3
CBC § 2109.2.4.8.7 High relevance — show source text
2109.2.4.8.7 Lime plaster. Lime plaster is any plaster with a binder composed of calcium hydroxide, including Type N or S hydrated lime, hydraulic lime, natural hydraulic lime, or slaked quicklime. Hydrated lime shall comply with ASTM C206. Hydraulic lime shall comply with ASTM C1707. Natural hydraulic lime shall comply with ASTM C141 and EN 459. Quicklime shall comply with ASTM C5.
2109.2.4.8.8 Cement-lime plaster. Cement-lime plaster shall be any plaster mix type CL, F or FL, as described in ASTM C926.
2109.2.4.8.9 Clay plaster. Clay plaster shall comply with this section.
2109.2.4.8.9.1 General. Clay plaster shall be any plaster having a clay or clay subsoil binder. Such plaster shall contain sufficient clay to fully bind the aggregate and shall be permitted to contain reinforcing fibers. Acceptable reinforcing fibers include chopped straw, sisal, and animal hair.
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2109.2.4.8.9.2 Clay subsoil requirements. The suitability of clay subsoil shall be determined in accordance with the Figure 2 Ribbon Test and the Figure 3 Ball Test in the appendix of ASTM E2392/E2392M.
2109.2.4.8.9.3 Weather-exposed locations. Clay plaster exposed to water from direct or wind-driven rain or snow shall be finished with an approved erosion-resistant finish. The use of clay plasters shall not be permitted on weather-exposed parapets.
2109.2.4.8.9.4 Prohibited finish coat. Plaster containing Portland cement shall not be permitted as a finish over clay plaster.
2109.2.4.8.9.5 Conditions where lathing is not required. For unstabilized adobe walls finished with unstabilized clay plaster, lathing shall not be required.
2109.2.4.9 Lintels. Lintels shall be considered to be structural members and shall be designed in accordance with the applicable provisions of Chapter 16.
SECTION 2110—GLASS UNIT MASONRY
2110.1 General. [OSHPD 1R, 2 & 5] Masonry glass block walls or panels shall be designed for seismic forces. Stresses in glass block shall not be utilized. Glass unit masonry construction shall comply with Chapter 14 of TMS 402 and this section.
2110.1.1 Limitations. Solid or hollow approved glass block shall not be used in fire walls, party walls, fire barriers, fire partitions or smoke barriers, or for load-bearing construction. Such blocks shall be erected with mortar and reinforcement in metal channeltype frames, structural frames, masonry or concrete recesses, embedded panel anchors as provided for both exterior and interior walls or other approved joint materials. Wood strip framing shall not be used in walls required to have a fire-resistance rating by other provisions of this code.
CBC § 406.8.2 High relevance — show source text
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INDEX
Gas detection system 406.8.2, 916 Sprinkler protection 406.8.3, 903.2.9.1 Ventilation 406.8.1
Garages, Truck and Bus Live load 1607.8
Sprinkler protection 903.2.10.1 Garages and Carports, Private Area limitations 406.3.1
Classification 406.3.1
Door openers 406.2.1 Door springs 1212 Parking surfaces 406.2.4 Separation 406.2.5, 406.3.2 Gas 101.4.1, 105.2, 112 Gas detection system 406.8.2, 415.11.8, 421.5, 916 Hydrogen cutoff room 421.6 Motor fuel-dispensing 406.7 Gates 1010.4
Vehicular 406.2.1, 3110 Gift Shops 407.2.4 Girders
Fire resistance Table 601
Materials Chapter 6 Wood construction 2304.12.1.1,
2308.8.1 Glass (see Glazing) Glass Block (see Glass Unit Masonry) Glass Mat Gypsum Panel Table 2506.2 Glass Unit Masonry 2110 Atrium enclosure 404.6
Fire resistance 2110.1.1
Hazardous locations 2406.1.3 Glazing Athletic facilities 2408
Atrium enclosure 404.6
Doors 705.9, 709.5, 710.5, 716.2.5.3, 1404.14, 1709.1 Elevator hoistway and car 2409.2, 2409.3, 2409.4 Fire doors 716.2.2.3.1, 716.2.5 Fire windows 703.3, 716.2.1 Group I-3 408.7 Guards 1015.2.1, 2406.4.4, 2407 Handrail 1011.11, 2407 Identification 2403.1, 2406.3 Impact loads 2406.1, 2408.2.1, 2408.3 Impact resistant 1609.2 Jalousies 2403.5 Label/identification 716.1.2.2.1, 716.1.2.2.2, 716.2.9.1, 716.2.9.5,
716.3.5.2
Loads 2404
Louvered windows 2403.5
Opening protection 716.1.2.3 Replacement 2402 Safety 716.1.2.1, 2406 Security 408.7 Skylights 2405 Sloped 2404.2, 2405 Supports 2403.2 Swimming pools 2406.4.5 Testing 1709.5, 2406.1.1, 2408.2.1 Veneer 1404.13
CBC § 303.1.1 High relevance — show source text
Roofs
Special Chapter 4 Occupancy Classification Chapter 3 Covered and open mall buildings 402
Detailed requirements Chapter 4 Exceptions 303.1.1, 303.1.4, 305.1.1, 305.2.1, 305.2.3, 307.1.1, 308.5.1, 308.5.4, 310.4.1, 311.1.1
HPM 415.11
Mixed 508, 510 Occupied roofs 302.1, 503.1.4 Occupancy Separation Accessory 508.2 Aircraft related 412.4.1 Nonseparated use method 508.3 Separated use method 508.4 Special provisions 510 Unlimited area buildings 507.1.1, 507.4.1, 507.8 Occupant Evacuation Elevators 403.5.2, 403.6.2, 3008 Occupant Load Business Table 1004.5, 1004.8 Calculated 1004.5 Certificate of occupancy 111 Covered and open mall building 402.8.2
Cumulative 1004.2
Increased 1004.5.1 Multiple function 1004.3 Multiple occupancies 1004.4 Outdoors 1004.7 Seating, fixed 1004.6 Signs 1004.9 Occupiable Roofs 503.1.4, 1004.7, 1006.3, 1009.2.1, 1607.14.2 Office Buildings (see Group B Occupancies) Classification 304
Live loads Table 1607.1, 1607.5 Open Mall Buildings (see Covered and Open Mall Buildings) Opening Protection, Exterior Walls 705.9 Opening Protection, Floors (see Vertical Opening Protection) Opening Protectives 705.9, 706.8, 707.6, 708.6, 709.5, 712.1.13.1, 713.7, 716 Automatic-closing devices 909.5.3 Fire door and shutter assemblies
705.9.2, 712.1.13.1, 716.2.1 Fire windows 716.3.4 Glass unit masonry (see Glass Unit Masonry) 2110.1.1 Glazing 716.1.2 Organic Coatings 418 Organic Peroxides 307.4, 307.5 Oxidizers, Liquid And Solid 307.3, 307.4,
307.5
Panic Hardware 1006.2.2.2, 1006.2.2.4, 1010.2.4, Table 1010.2.4, 1010.2.7, 1010.2.8,
1010.4.1
Parapet, Exterior Wall 705.12, 2109.2.4.3 Construction 705.12.1
CBC § 4.1 High relevance — show source text
1705 A .4.1 Glass unit masonry and masonry veneer in Risk Category II, III or IV. Special inspections and tests for glass unit masonry or masonry veneer designed in accordance with Section 2110 A or Chapter 14, respectively, where they are part of a structure classified as Risk Category II, III or IV shall be performed in accordance with TMS 602 Tables 3 and 4, Level 2.
1705A.4.1.1 TMS 602 Section 1.6 Quality Assurance. Replace footnote (d) in TMS 602 Table 4 as follows:
(d) Periodic special inspection is required for all veneer.
1705 A .4.2 Vertical masonry foundation elements. Special inspections and tests of vertical masonry foundation elements shall be performed in accordance with Section 1705 A .4.
1705 A .5 Wood construction. Special inspections of prefabricated wood structural elements and assemblies shall be in accordance with Section 1704 A .2.5 except as modified in this section . Special inspections of site-built assemblies shall be in accordance with this section.
1705 A .5.1 High-load diaphragms. High-load diaphragms designed in accordance with Section 2306.2 or 2307.1 shall be installed with special inspections as indicated in Section 1704 A .2. The special inspector shall inspect the wood structural panel sheathing to ascertain whether it is of the grade and thickness shown on the approved construction documents. Additionally, the special inspector must verify the nominal size of framing members at adjoining panel edges, the nail or staple diameter and length, the number of fastener lines and that the spacing between fasteners in each line and at edge margins agrees with the approved construction documents.
1705 A .5.2 Metal-plate-connected wood trusses spanning 60 feet or greater. Where a truss clear span is 60 feet (18 288 mm) or greater, the special inspector shall verify that the temporary installation restraint/bracing and the permanent individual truss member restraint/bracing are installed in accordance with the approved truss submittal package.
1705 A .5.3 Mass timber construction. Special inspections of mass timber elements in Types IV-A, IV-B and IV-C construction shall be in accordance with Table 1705 A .5.3.
2025 CALIFORNIA BUILDING CODE 17A-13
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
SPECIAL INSPECTIONS AND TESTS
TABLE 1705A.5.3—REQUIRED SPECIAL INSPECTIONS OF MASS TIMBER CONSTRUCTION Col2 Col3 Col4 TYPE TYPE CONTINUOUS
SPECIAL
INSPECTIONPERIODIC
SPECIAL
INSPECTION1. Inspection of anchorage and connections of mass timber construction to timber deep foundation
systems.— X 2. Inspect erection of mass timber construction. — X 3. Inspection of connections where installation methods are required to meet design loads. _3.1. CBC § 1705.3.9.1 Medium relevance — show source text
1705.3.9.1 Visual examination for structural soundness of in-place shotcrete. Completed shotcrete work shall be checked visu- ally for reinforcing bar embedment, voids, rock pockets, sand streaks and similar deficiencies by examining a minimum of three 3- inch (76 mm) cores taken from three areas chosen by the design engineer which represent the worst congestion of reinforcing bars occurring in the project. Extra reinforcing bars may be added to noncongested areas and cores may be taken from these areas. The cores shall be examined by the special inspector and a report submitted to the enforcement agency prior to final approval of the shotcrete.
Exception: Shotcrete work fully supported on earth, minor repairs, and when, in the opinion of the enforcement agency, no special hazard exists.
1705.3.9.2 Preconstruction tests. A shotcrete mockup panel shall be shot, cured, cored or sawn, examined and tested prior to commencement of the project. The mockup panel shall be representative of the project and simulate job conditions as closely as possible. The mockup panel thickness and reinforcing shall reproduce the thickest and most congested area specified in the struc- tural design. It shall be shot at the same angle, using the same nozzleman and with the same concrete mix design that will be used on the project. Adequate encasement of bars larger than No. 5 shall be demonstrated by the mockup panels. The equipment used in preconstruction testing shall be the same equipment used in the work requiring such testing, unless substitute equipment is approved by the building official. Reports of preconstruction tests shall be submitted to the building official as specified in Section 1704.5.
1705.4 Masonry construction. Special inspections and tests of masonry construction shall be performed in accordance with the quality assurance program requirements of TMS 402 and TMS 602. [OSHPD 1R, 2 & 5] as set forth in Tables 3 and 4, Level 3 require- ments and Chapter 21. Testing shall be performed in accordance with Section 2105. Special inspection and testing of post-installed anchors in masonry shall be required in accordance with requirements for concrete in Chapters 17 and 19. Batch plant inspection of grout materials shall be in accordance with Section 1705.3.3.
Exception: [OSHPD 1R, 2 & 5] Not permitted by OSHPD. Special inspections and tests shall not be required for:
- Glass unit masonry or masonry veneer designed in accordance with Section 2110 or Chapter 14, respectively, where they are part of a structure classified as Risk Category I, II or III.
- Masonry foundation walls constructed in accordance with Table 1807.1.6.3(1), 1807.1.6.3(2), 1807.1.6.3(3) or 1807.1.6.3(4).
- Masonry fireplaces, masonry heaters or masonry chimneys installed or constructed in accordance with Section 2111, 2112 or 2113, respectively.
CBC § 1705.4 Medium relevance — show source text
5 shall be demonstrated by the mockup panels. The equipment used_ in preconstruction testing shall be the same equipment used in the work requiring such testing, unless substitute equipment is approved by the building official. Reports of preconstruction tests shall be submitted to the building official as specified in Section 1704.5.
1705.4 Masonry construction. Special inspections and tests of masonry construction shall be performed in accordance with the quality assurance program requirements of TMS 402 and TMS 602. [OSHPD 1R, 2 & 5] as set forth in Tables 3 and 4, Level 3 require- ments and Chapter 21. Testing shall be performed in accordance with Section 2105. Special inspection and testing of post-installed anchors in masonry shall be required in accordance with requirements for concrete in Chapters 17 and 19. Batch plant inspection of grout materials shall be in accordance with Section 1705.3.3.
Exception: [OSHPD 1R, 2 & 5] Not permitted by OSHPD. Special inspections and tests shall not be required for:
- Glass unit masonry or masonry veneer designed in accordance with Section 2110 or Chapter 14, respectively, where they are part of a structure classified as Risk Category I, II or III.
- Masonry foundation walls constructed in accordance with Table 1807.1.6.3(1), 1807.1.6.3(2), 1807.1.6.3(3) or 1807.1.6.3(4).
- Masonry fireplaces, masonry heaters or masonry chimneys installed or constructed in accordance with Section 2111, 2112 or 2113, respectively.
1705.4.1 Glass unit masonry and masonry veneer in Risk Category IV. Special inspections and tests for glass unit masonry or masonry veneer designed in accordance with Section 2110 or Chapter 14, respectively, where they are part of a structure classified as Risk Category IV shall be performed in accordance with TMS 602 Level 2. [OSHPD 1R, 2 & 5] Not permitted by OSHPD.
[OSHPD 1R, 2 & 5] Glass unit masonry and masonry veneer in Risk Category II, III or IV. Special inspections and tests for glass unit masonry or masonry veneer designed by Section 2110 or Chapter 14, respectively, in structures classified as Risk Category II, III or IV, shall be performed in accordance with TMS 602 Tables 3 and 4, Level 2 Quality Assurance.
1705.4.1.1 TMS 602 Section 1.6 Quality Assurance. [OSHPD 1R, 2 & 5] Replace footnote (d) as follows: (d) Periodic special inspection is required for all veneer.
1705.4.2 Vertical masonry foundation elements. Special inspections and tests of vertical masonry foundation elements shall be performed in accordance with Section 1705.4.
1705.5 Wood construction. Special inspections of prefabricated wood structural elements and assemblies shall be in accordance with Section 1704.2.5. Special inspections of site-built assemblies shall be in accordance with this section.
Frequently asked questions
Can glass block be used as a load‑bearing wall?
No. Glass block is not permitted for load‑bearing construction; the frame or surrounding structure must carry loads and glass block stresses must not be used for structural design (§ 2110.1).
Can I use glass block in a 1‑hour fire barrier?
Only if the glass‑block assembly is a listed opening protective with a fire protection rating of at least 3/4 hour and other exception conditions are met (see Exception 1 to § 2110.1.1 and Section 716).
Are special inspections required for glass unit masonry?
Yes for higher risk projects: glass unit masonry in structures classified as Risk Category II, III or IV is subject to the special inspection and TMS 602 quality assurance provisions referenced in § 1705.4.1.
Is Portland cement plaster allowed over clay (adobe) plaster?
No. The CBC prohibits plaster containing Portland cement as a finish coat over clay plaster (§ 2109.2.4.8.9.4).
Do adobe walls always require lath before plastering?
No. For unstabilized adobe walls finished with unstabilized clay plaster, lathing is not required (§ 2109.2.4.8.9.5).
More in California Building Code
- Administration & Permits
- Energy Efficiency
- Existing Buildings
- Occupancy Classification & Use
- Hazardous Materials & Occupancies
- Types of Construction
- Fire-Resistance & Fire Safety
- Interior Finishes
- Means of Egress
- Accessibility
- Exterior Walls
- Roofing & Roof Assemblies
- Structural Design
- Special Inspections & Tests
- Foundations & Soils
- Concrete
- Masonry
- Steel
- Wood
- Elevators & Conveying Systems
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