CBC · California Building Code

Protection against decay and subterranean termites

Q: Do I always have to use pressure‑treated wood near foundations?

If the wood location meets the CBC thresholds (for example, joists < 18 in. from exposed ground or wood framing < 8 in. from exposed earth at exterior foundation walls), the CBC requires either naturally durable wood or preservative‑treated wood for that location per § 2304.12.1.1 and § 2304.12.1.2 .

Q: Is a concrete slab next to a sill always an automatic exception?

No. The exception that allows sills 6 in. above a slab applies only where the slab is at least 18 in. wide and drains away from the building; otherwise the 8‑inch clearance or treated/naturally durable wood requirement applies (§ 2304.12.1.2).

Q: What standard defines acceptable preservative treatments?

The CBC references AWPA U1 (and AWPA end‑use designations) for waterborne and soil/freshwater treatments; use products and markings that comply with AWPA and the manufacturer’s instructions as applicable (see §§ 2304.12.1 and 2304.12.2.6).

Q: If I buy preservative‑treated lumber, do I need to retreat any field cuts?

Yes; field‑cut ends, notches and drilled holes on preservative‑treated wood should be field‑treated consistent with industry standards (AWPA M4 is referenced in the Residential Code for dwellings). Check the project scope to determine the correct standard and marking requirements.

Q: Where can I propose an alternative to treated wood?

The CBC allows the enforcement agency (building official) to accept other equivalent methods of termite and decay protection at their discretion; provide documentation and an approved alternative protection method for review (see exceptions / agency acceptance language in § 2304.12.1.2).

For homeowners: the CBC requires wood near the ground or foundation to be naturally decay/termite‑resistant or preservative‑treated. Key numbers to remember: keep joists at least 18 inches above exposed ground (12 inches minimum for other horizontal members for inspection), use treated or durable wood if closer than the listed clearances, and note the 8‑inch rule for wood next to foundation walls (with a specific 6‑inch exception over a wide, draining paved slab). Check the cited CBC sections and local enforcement for acceptable alternatives.

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Last reviewed: July 5, 2026

What the code requires

The California Building Code requires that wood be protected from decay and subterranean termites by using naturally durable species or preservative‑treated wood in specified locations, and by providing minimum clearances between wood and exposed earth or slabs where applicable — see § 2304.12 for the general rule and the location‑specific requirements in § 2304.12.1 and § 2304.12.2. The CBC also specifies particular clearance distances and an exception for sills over paved slabs; see § 2304.12.1.2 for wood supported by exterior foundation walls.

Requirements in detail

Scope and referenced treatment standards

The general requirement is stated in § 2304.12: wood shall be protected from decay and termites in accordance with Sections 2304.12.1 through 2304.12.4. The CBC references AWPA U1 for waterborne preservative treatment for above‑ground and soil/freshwater use where required.

Location‑based rules and numeric thresholds

Crawlspace floor joists and subfloor members: Wood joists or wood structural floors that are closer than 18 inches (457 mm) to exposed ground in crawl spaces (or wood girders closer than 12 inches / 305 mm) must be naturally durable or preservative‑treated (§ 2304.12.1.1 and § 2304.12.1.1.1). The code also establishes minimum clearances for inspection and grading of the ground beneath joists.
Wood supported by exterior foundation walls: Wood framing members (including sheathing) that are in contact with exterior foundation walls and are less than 8 inches (203 mm) from exposed earth must be naturally durable or preservative‑treated (§ 2304.12.1.2). The CBC provides an exception where a paved slab ≥ 18 inches (457 mm) wide drains away from the building, permitting sill bottoms 6 inches (152 mm) above the slab top as an approved alternative in those circumstances.
Wood siding clearance: Exterior wood siding must be kept at least 6 inches (152 mm) above exposed earth, or at least 2 inches (51 mm) above concrete steps, porch slabs, patio slabs and similar horizontal surfaces exposed to the weather — unless siding/sheathing/framing are of naturally durable or preservative‑treated wood (§ 2304.12.1.5).
Ground contact and freshwater contact: Wood used in contact with exposed earth must be preservative‑treated or naturally durable for both decay and termite resistance, in accordance with AWPA U1 for soil/freshwater use (§ 2304.12.2.6). The code notes an exception where untreated wood may be permitted if it is continuously and entirely below the groundwater level or submerged in fresh water.
Heavy termite hazard locations: In areas known to have a very heavy hazard of termite damage, the CBC requires pressure‑preservative treated wood or naturally durable species for specified floor framing locations and exposed deck/balcony framing, or approved alternative termite protection methods (§ 2304.12.2.7).

Decision table (quick reference)

Condition / measurement	Required protection or action	Code Reference
Wood joists / structural floors < 18 in (457 mm) above exposed ground in crawl spaces	Use naturally durable wood or preservative‑treated wood	§ 2304.12.1.1
Wood girders < 12 in (305 mm) above exposed ground in crawl spaces	Use naturally durable wood or preservative‑treated wood	§ 2304.12.1.1
Wood framing (incl. sheathing) in contact with exterior foundation walls and < 8 in (203 mm) from exposed earth	Use naturally durable wood or preservative‑treated wood	§ 2304.12.1.2
Sill over paved slab (asphalt/concrete slab ≥ 18 in / 457 mm wide and draining away)	Bottom of sills permitted 6 in (152 mm) above slab (exception)	§ 2304.12.1.2 exception
Clearance between wood siding and exposed earth	≥ 6 in (152 mm) (or ≥ 2 in / 51 mm above concrete steps/slabs) unless wood is durable/treated	§ 2304.12.1.5
Wood in contact with exposed earth or freshwater	Use preservative‑treated or naturally durable wood per AWPA U1; untreated allowed only if permanently submerged/continuously below groundwater	§ 2304.12.2.6
Areas of very heavy termite hazard (floor framing, decks/balconies)	Pressure‑preservative treated or naturally termite‑resistant wood, or approved termite protection	§ 2304.12.2.7

(When the code requires “preservative‑treated,” the CBC references treatment standards such as AWPA U1 for the correct treatment and end‑use. See the cited sections for the referenced standards.)

Exceptions & special cases

Paved slab exception for exterior sills: Where exterior earth adjacent to an exterior wall is paved with an asphalt or concrete slab at least 18 inches (457 mm) wide that drains away from the building, the bottom of sills may be 6 inches (152 mm) above the slab top instead of meeting the 8‑inch soil clearance requirement — this is an explicit exception in § 2304.12.1.2. Enforcement agencies may accept other equivalent termite/decay protections as well.
Submerged members: Untreated wood that is continuously and entirely below groundwater level or submerged in fresh water may be permitted without preservative treatment (§ 2304.12.2.6).
Local enforcement discretion: The building official can accept “other equivalent means” of termite/decay protection; project‑specific details (drainage, ventilation, and finish grades) affect which exceptions or alternatives are acceptable. See the applicable § cited above for the text and the local enforcement agency for determinations.

Note: I was able to retrieve and ground the CBC text for § 2304.12 and § 2304.12.1.2 from the supplied CBC files. I could not retrieve an explicit copy of § 2304.12.2.1 from the files provided; therefore I cannot state its text or apply it here. If you need § 2304.12.2.1 specifically, I can search the provided files again or you can supply that page.

Common mistakes

Misreading clearance numbers: failing to distinguish 18 in. (joists) vs 12 in. (other horizontal framing) vs 8 in. (wood adjacent to foundation walls) leads to noncompliance. Always cite the exact § (see § 2304.12.1.1 and § 2304.12.1.2).
Assuming “treated” equals any treatment: the CBC references AWPA U1 and specific use categories (above‑ground vs soil/freshwater). Use products and marks compliant with the referenced standard; check manufacturer labels and AWPA end‑use designations.
Forgetting field treatment: where preservative‑treated members are field‑cut, notches and holes generally require field retreatment per the applicable standards — the Residential Code explicitly requires field retreatment per AWPA M4 for treated lumber used in dwellings (see R305.1.2 for field treatment guidance in residential projects).
Ignoring drainage and ventilation: treating wood is only one part; controlling moisture (positive drainage away from the foundation, under‑floor ventilation in crawl spaces per §§ 1202.4 / 2304.12.4) is critical. The code links protection to site conditions and ventilation requirements.

Worked example

Scenario: Single‑story house with crawlspace. The underside of floor joists measures 14 inches above the finished ground surface in the crawlspace. Exterior foundation walls are adjacent to soil; the bottom of the sill plate is 7 inches above the top of an adjacent concrete patio slab (the slab is 14 inches wide and slopes toward the house).

Apply the CBC:

Joist clearance: 14 in. < 18 in., so the joists / subfloor are in the category requiring naturally durable or preservative‑treated wood — per § 2304.12.1.1. The joists must be treated or be of naturally durable species.
Foundation wall/sill: the sill is 7 in. above a concrete slab that is only 14 in. wide. § 2304.12.1.2 requires wood in contact with exterior foundation walls that are less than 8 in. from exposed earth to be durable or treated. The exception permitting sills 6 in. above a paved slab requires the slab to be at least 18 in. wide and draining away; neither condition is met (slab only 14 in., slopes toward house), so the sill must be preservative‑treated or made of a naturally durable species. § 2304.12.1.2 exception does not apply.
Remediation options: raise the finished ground or add an approved impervious barrier and drainage that meets the exception, or replace/retrofit the joists and sill with preservative‑treated lumber. Discuss alternatives with the enforcement agency if other equivalent termite/decay protection is proposed.

Related provisions

§ 2304.12 — General protection against decay and termites (see chapter introduction and scope).
§ 2304.12.1.1 and § 2304.12.1.1.1 — Joist, girder, subfloor clearances and under‑floor clearance guidance.
§ 2304.12.1.5 — Clearance requirements for wood siding above exposed earth and slabs.
§ 2304.12.2.6 — Requirements for wood in contact with the ground or fresh water (soil/freshwater treatment).
§ 2304.12.2.7 — Termite protection in areas of very heavy hazard; decks and exposed framing.
CBC cross‑references to AWPA U1 (treatment standards) — see references in §§ 2304.12.1 and 2304.12.2.6.
Residential Code R305 (Protection Against Subterranean Termites) — for site‑specific termite controls, chemical treatments, baiting, and barriers in residential construction.

Code references

Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:

CBC § 2304.11.4.1 High relevance — show source text
2304.11.4.1 Cross-laminated timber roofs. Cross-laminated timber roofs shall be not less than 3 inches (76 mm) in thickness and shall be continuous from support to support and mechanically fastened to one another.

2304.11.4.2 Sawn, wood structural panel, or glued-laminated plank roofs. Sawn, wood structural panel, or glued-laminated plank roofs shall be one of the following:
1. Sawn or glued laminated, splined or tongue-and-groove plank, not less than 2 inches (51 mm) nominal in thickness.
2. 1 [1] / 8 -inch-thick (32 mm) wood structural panel (exterior glue).
3. Planks not less than 3 inches (76 mm) nominal in width, set on edge close together and laid as required for floors.
2304.12 Protection against decay and termites. Wood shall be protected from decay and termites in accordance with the applicable provisions of Sections 2304.12.1 through 2304.12.4.

2304.12.1 Locations requiring waterborne preservatives or naturally durable wood. Wood used above ground in the locations specified in Sections 2304.12.1.1 through 2304.12.1.5 shall be naturally durable wood or preservative-treated wood using waterborne preservatives, in accordance with AWPA U1 for above-ground use.

2025 CALIFORNIA BUILDING CODE 23-23

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

WOOD

2304.12.1.1 Joists, girders and subfloor. Wood joists or wood structural floors that are closer than 18 inches (457 mm) or wood girders that are closer than 12 inches (305 mm) to the exposed ground in crawl spaces or unexcavated areas located within the perimeter of the building foundation shall be of naturally durable or preservative-treated wood.

2304.12.1.1.1 [SPCB] There shall be a clearance of at least 18 inches (457 mm) between the underside of wood floor joists and the finished surface of the ground, and at least 12 inches (305 mm) between the underside of any other wood horizontal framing member and the finished surface of the ground. The ground underneath floor joists shall be leveled or smoothed off so as to maintain a reasonably even surface.

Exception: For purposes of structural pest control inspection, a minimum of 12 inches (305 mm) of clearance under-floor joists shall be considered adequate except that such clearance shall not be necessary where the subarea soil is of such a nature as to prevent excavation or where excavation would create a hazard from shifting soil or other causes.

2304.12.1.2 Wood supported by exterior foundation walls. Wood framing members, including wood sheathing, that are in contact with exterior foundation walls and are less than 8 inches (203 mm) from exposed earth shall be of naturally durable or preservative-treated wood.

Exception: [DSA-SS and OSHPD 1, 1R, 2, 4 & 5] At exterior walls where the earth is paved with an asphalt or concrete slab at least 18 inches (457 mm) wide and draining away from the building, the bottom of sills are permitted to be 6 inches (152 mm) above the top of such slab. Other equivalent means of termite and decay protection may be accepted by the enforcement agency.
CBC § 3-34 High relevance — show source text
3-34 2025 CALIFORNIA RESIDENTIAL CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

BUILDING PLANNING

R304.3.2 Fastenings for wood foundations. Fastenings, including nuts and washers, for wood foundations shall be as required in AWC PWF.

R304.3.3 Fasteners for fire-retardant-treated wood used in exterior applications or wet or damp locations. Fasteners, including nuts and washers, for fire-retardant-treated wood used in exterior applications or wet or damp locations shall be of hot-dipped, zinc-coated galvanized steel, stainless steel, silicon bronze or copper. Fasteners other than nails, staples and timber rivets shall be permitted to be of mechanically deposited zinc-coated steel with coating weights in accordance with ASTM B695, Class 55 minimum.

R304.3.4 Fasteners for fire-retardant-treated wood used in interior applications. Fasteners, including nuts and washers, for fire-retardant-treated wood used in interior locations shall be in accordance with the manufacturer’s recommendations. In the absence of the manufacturer’s recommendations, Section R304.3.3 shall apply.

R304.4 Plastic composites. Plastic composite exterior deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall comply with the requirements of Section R507.2.2.

SECTION R305—PROTECTION AGAINST SUBTERRANEAN TERMITES

R305.1 Subterranean termite control methods. In areas subject to damage from termites as indicated by Table R301.2, protection shall be by one, or a combination, of the following methods:
1. Chemical termiticide treatment in accordance with Section R305.2.
2. Termite-baiting system installed and maintained in accordance with the label.
3. Pressure-preservative-treated wood in accordance with the provisions of Section R304.1.
4. Naturally durable termite-resistant wood.
5. Physical barriers in accordance with Section R305.3 and used in locations as specified in Section R304.1.
6. Cold-formed steel framing in accordance with Sections R505.2.1 and R603.2.1.
R305.1.1 Quality mark. Lumber and plywood required to be pressure-preservative treated in accordance with Section R305.1 shall bear the quality mark of an approved inspection agency that maintains continuing supervision, testing and inspection over the quality of the product and that has been approved by an accreditation body that complies with the requirements of the American Lumber Standard Committee treated wood program.

R305.1.2 Field treatment. Field-cut ends, notches and drilled holes of pressure-preservative-treated wood shall be retreated in the field in accordance with AWPA M4.

R305.2 Chemical termiticide treatment. Chemical termiticide treatment shall include soil treatment or field-applied wood treatment. The concentration, rate of application and method of treatment of the chemical termiticide shall be in strict accordance with the termiticide label.

R305.3 Barriers. Approved physical barriers, such as metal or plastic sheeting or collars specifically designed for termite prevention, shall be installed in a manner to prevent termites from entering the structure. Shields placed on top of an exterior foundation wall shall be used only if in combination with another method of protection.
CBC § 2304.11.3.2 High relevance — show source text
2304.11.3.2 Sawn or glued-laminated plank floors. Sawn or glued-laminated plank floors shall be one of the following:
1. Sawn or glued-laminated planks, splined or tongue-and-groove, of not less than 3 inches (76 mm) nominal in thick ness covered with 1-inch (25 mm) nominal dimension tongue-and-groove flooring, laid crosswise or diagonally, [15] / 32
inch (12 mm) wood structural panel or [1] / 2 -inch (12.7 mm) particleboard. 2. Planks not less than 4 inches (102 mm) nominal in width set on edge close together and well spiked and covered with 1-inch (25 mm) nominal dimension flooring or [15] / 32 -inch (12 mm) wood structural panel or [1] / 2 -inch (12.7 mm) particleboard.

The lumber shall be laid so that continuous lines of joints will occur only at points of support. Floors shall not extend closer than [1] / 2 inch (12.7 mm) to walls. Such [1] / 2 -inch (12.7 mm) space shall be covered by a molding fastened to the wall and so arranged that it will not obstruct the swelling or shrinkage movements of the floor. Corbelling of masonry walls under the floor shall be permitted to be used in place of molding.

2304.11.4 Roof decks. Roofs shall be without concealed spaces or with concealed spaces complying with Section 602.4.4.3. Roof decks shall be constructed in accordance with Section 2304.11.4.1 or 2304.11.4.2. Other types of decking shall be an alternative that provides equivalent fire resistance and structural properties. Where supported by a wall, roof decks shall be anchored to walls to resist forces determined in accordance with Chapter 16. Such anchors shall consist of steel bolts, lags, screws or approved hardware of sufficient strength to resist prescribed forces.

2304.11.4.1 Cross-laminated timber roofs. Cross-laminated timber roofs shall be not less than 3 inches (76 mm) in thickness and shall be continuous from support to support and mechanically fastened to one another.

2304.11.4.2 Sawn, wood structural panel, or glued-laminated plank roofs. Sawn, wood structural panel, or glued-laminated plank roofs shall be one of the following:
1. Sawn or glued laminated, splined or tongue-and-groove plank, not less than 2 inches (51 mm) nominal in thickness.
2. 1 [1] / 8 -inch-thick (32 mm) wood structural panel (exterior glue).
3. Planks not less than 3 inches (76 mm) nominal in width, set on edge close together and laid as required for floors.
2304.12 Protection against decay and termites. Wood shall be protected from decay and termites in accordance with the applicable provisions of Sections 2304.12.1 through 2304.12.4.

2304.12.1 Locations requiring waterborne preservatives or naturally durable wood. Wood used above ground in the locations specified in Sections 2304.12.1.1 through 2304.12.1.5 shall be naturally durable wood or preservative-treated wood using waterborne preservatives, in accordance with AWPA U1 for above-ground use.

2025 CALIFORNIA BUILDING CODE 23-23
CBC § 3-33 High relevance — show source text
R304 Protection of Wood and Wood-Based Products

Against Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33

R305 Protection Against Subterranean Termites. . . . . . . 3-35

R306 Flood-Resistant Construction. . . . . . . . . . . . . . . . . . . 3-36

R307 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

R308 Site Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

R309 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . 3-41

R310 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54

R311 Carbon Monoxide Alarms. . . . . . . . . . . . . . . . . . . . . . . 3-58

R312 Minimum Room Areas . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

R313 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

R314 Mezzanines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

R315 Sleeping Lofts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

R316 Habitable Attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

R317 Garages and Carports. . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

R318 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-62

R319 Emergency Escape and Rescue Openings . . . . . . . . 3-65

R320 Handrails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-67

R321 Guards and Window Fall Protection . . . . . . . . . . . . . 3-67

R322 Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

R323 Elevators and Platform Lifts . . . . . . . . . . . . . . . . . . . . 3-68

R324 Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68
CBC § 4.3. High relevance — show source text
4.3. In hurricane-prone regions and flood hazard areas, such units are designed in accordance with the applicable provisions of Chapter 16. 5. [HCD] Shipping containers constructed or converted off-site that meet the definition of Factory-built Housing in Health and Safety Code Section 19971 or Commercial Modular(s) as defined in Health and Safety Code Section 18001.8 shall be approved by the Department of Housing and Community Development.

3114.2 Construction documents. The construction documents shall contain information to verify the dimensions and establish the physical properties of the steel components and wood floor components of the intermodal shipping container, in addition to the information required by Sections 107 and 1603.

3114.3 Intermodal shipping container information. Intermodal shipping containers shall bear an existing data plate containing the following information as required by ISO 6346 and verified by an approved agency. A report of the verification process and findings shall be provided to the building owner.
1. Manufacturer’s name or identification number.
2. Date manufactured.
3. Safety approval number.
4. Identification number.
5. Maximum operating gross mass or weight (kg) (lbs).
6. Allowable stacking load for 1.8G (kg) (lbs).
7. Transverse racking test force (Newtons).
8. Valid maintenance examination date.
Where approved by the building official, the markings and existing data plate are permitted to be removed from the intermodal shipping containers before they are repurposed for use as buildings or structures or as a part of buildings or structures.

3114.4 Protection against decay and termites. Wood structural floors of intermodal shipping containers shall be protected from decay and termites in accordance with the applicable provisions of Section 2304.12.1.1.

3114.5 Under-floor ventilation. The space between the bottom of the floor joists and the earth under any intermodal shipping container, except spaces occupied by basements and cellars, shall be provided with ventilation in accordance with Section 1202.4.

3114.6 Roof assemblies. Intermodal shipping container roof assemblies shall comply with the applicable requirements of Chapter 15.

Exception: Single-unit, stand-alone intermodal shipping containers not attached to, or stacked vertically over, other intermodal shipping containers, buildings or structures. [DSA-SS & DSA-SS/CC] Not permitted by DSA.

3114.7 Joints and voids. Joints and voids that create concealed spaces between connected or stacked intermodal shipping containers at fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system in accordance with Section 715.

3114.8 Structural. Intermodal shipping containers that conform to ISO 1496-1 and are repurposed for use as buildings or structures, or as a part of buildings or structures, shall be designed in accordance with Chapter 16 and this section.

3114.8.1 Foundations and supports. Intermodal shipping containers repurposed for use as a permanent building or structure shall be supported on foundations or other supporting structures designed and constructed in accordance with Chapters 16 through 23.

3114.8.1.1 Anchorage. Intermodal shipping containers shall be anchored to foundations or other supporting structures as necessary to provide a continuous load path for all applicable design and environmental loads in accordance with Chapter 16.

3114.8.1.2 Stacking. Intermodal shipping containers used to support stacked units shall comply with Section 3114.8.4.
CBC § 3114.1 High relevance — show source text
SECTION 3114—INTERMODAL SHIPPING CONTAINERS

[OSHPD 1, 1R, 2, 4 & 5] Not permitted by OSHPD.

3114.1 General. The provisions of Section 3114and other applicable sections of this code shall apply to intermodal shipping containers that are repurposed for use as buildings or structures, or as a part of buildings or structures.

Exceptions: [DSA-SS & DSA-SS/CC] Not permitted by DSA.
1. Intermodal shipping containers previously approved as existing relocatable buildings complying with Chapter 14 of the California Existing Building Code.
2. Stationary storage battery arrays located in intermodal shipping containers complying with Chapter 12 of the California Fire Code.
3. Intermodal shipping containers that are listed as equipment complying with the standard for equipment, such as air chillers, engine generators, modular data centers, and other similar equipment.
2025 CALIFORNIA BUILDING CODE 31-13

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

SPECIAL CONSTRUCTION
1. Intermodal shipping containers housing or supporting experimental equipment are exempt from the requirements of Section 3114, provided that they comply with all of the following: 4.1. Such units shall be single stand-alone units supported at grade level and used only for occupancies as specified under Risk Category I in Table 1604.5. 4.2. Such units are located a minimum of 8 feet (2438 mm) from adjacent structures, and are not connected to a fuel gas system or fuel gas utility. 4.3. In hurricane-prone regions and flood hazard areas, such units are designed in accordance with the applicable provisions of Chapter 16. 5. [HCD] Shipping containers constructed or converted off-site that meet the definition of Factory-built Housing in Health and Safety Code Section 19971 or Commercial Modular(s) as defined in Health and Safety Code Section 18001.8 shall be approved by the Department of Housing and Community Development.
3114.2 Construction documents. The construction documents shall contain information to verify the dimensions and establish the physical properties of the steel components and wood floor components of the intermodal shipping container, in addition to the information required by Sections 107 and 1603.

3114.3 Intermodal shipping container information. Intermodal shipping containers shall bear an existing data plate containing the following information as required by ISO 6346 and verified by an approved agency. A report of the verification process and findings shall be provided to the building owner.
1. Manufacturer’s name or identification number.
2. Date manufactured.
3. Safety approval number.
4. Identification number.
5. Maximum operating gross mass or weight (kg) (lbs).
6. Allowable stacking load for 1.8G (kg) (lbs).
7. Transverse racking test force (Newtons).
8. Valid maintenance examination date.
Where approved by the building official, the markings and existing data plate are permitted to be removed from the intermodal shipping containers before they are repurposed for use as buildings or structures or as a part of buildings or structures.

3114.4 Protection against decay and termites. Wood structural floors of intermodal shipping containers shall be protected from decay and termites in accordance with the applicable provisions of Section 2304.12.1.1.
CBC § 2-5 High relevance — show source text
Part II—Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

R201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

R202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Part III—Building Planning and Construction . . . . . . . . . . . .3-5

CHAPTER 3 BUILDING PLANNING . . . . . . . . . . . . . . . . . . . . .3-5

R300 Site Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

R301 Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

R302 Fire-Resistant Construction . . . . . . . . . . . . . . . . . . . . 3-23

R303 Foam Plastic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-31

R304 Protection of Wood and Wood-Based Products

Against Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33

R305 Protection Against Subterranean Termites. . . . . . . 3-35

R306 Flood-Resistant Construction. . . . . . . . . . . . . . . . . . . 3-36

R307 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

R308 Site Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

R309 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . 3-41

R310 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54

R311 Carbon Monoxide Alarms. . . . . . . . . . . . . . . . . . . . . . . 3-58

R312 Minimum Room Areas . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

R313 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59
CBC § 2304.12.2.4 High relevance — show source text
Exception: Sawn lumber in buildings located in a geographical region where experience has demonstrated that climatic conditions preclude the need to use durable materials where the structure is exposed to the weather.

2304.12.2.4 Supporting members for permeable floors and roofs. Wood structural members that support moisture-permeable floors or roofs that are exposed to the weather, such as concrete or masonry slabs, shall be of naturally durable or preservative-treated wood unless separated from such floors or roofs by an impervious moisture barrier. The impervious moisture barrier system protecting the structure supporting floors shall provide positive drainage of water that infiltrates the moisture-permeable floor topping.

2304.12.2.5 Ventilation beneath balcony or elevated walking surfaces. Enclosed framing in exterior balconies and elevated walking surfaces that have weather-exposed surfaces shall be provided with openings that provide a net free cross-ventilation area not less than [1] / 150 of the area of each separate space.

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2304.12.2.6 Wood in contact with the ground or fresh water. Wood used in contact with exposed earth shall be naturally durable for both decay and termite resistance or preservative treated in accordance with AWPA U1 for soil or freshwater use.

Exception: Untreated wood is permitted where such wood is continuously and entirely below the ground-water level or submerged in fresh water.

2304.12.2.6.1 Posts or columns. Posts and columns that are supporting permanent structures and embedded in concrete that is exposed to the weather or in direct contact with the earth shall be of preservative-treated wood.

2304.12.2.7 Termite protection. In geographical areas where hazard of termite damage is known to be very heavy, wood floor framing in the locations specified in Section 2304.12.1.1 and exposed framing of exterior decks or balconies shall be of naturally durable species (termite resistant) or preservative treated in accordance with AWPA U1 for the species, product preservative and end use or provided with approved methods of termite protection.

2304.12.2.8 Wood used in retaining walls and cribs. Wood installed in retaining or crib walls shall be preservative treated in accordance with AWPA U1 for soil and freshwater use.

2304.12.3 Attic ventilation. For attic ventilation, see Section 1202.2.2.

2304.12.4 Under-floor ventilation (crawl space). For under-floor ventilation (crawl space), see Section 1202.4.

2304.12.8 Separate wood framing. [SPCB] Correct the conditions in frame and stucco walls and similar appurtenant construction so that the wood framing is separate from the main structure by a complete concrete or masonry plug with no voids that will allow infestations to enter the structure from the wall. If there is no plug, the foundation shall be 2 inches (51 mm) or more above the grade levels and at least as high as the adjoining slabs or 4-inch (102 mm) concrete barrier seat off installed.
CBC § 2.1 High relevance — show source text
R507.2 Materials. Materials used for the construction of decks shall comply with this section.

R507.2.1 Wood materials. Wood structural members shall be protected from decay where required by Sections R304.1 and R304.1.2, and protected from termites where required by Section R305.1. Where design in accordance with Section R301 is provided, wood structural members shall be designed using the wet service factor defined in AWC NDS. Sawn lumber for joists, beams and posts shall be No. 2 or better. Cuts, notches and drilled holes of preservative-treated wood members shall be treated in accordance with Section R304.1.1.

R507.2.1.1 Engineered wood products. Engineered wood products shall be in accordance with Section R502.

R507.2.2 Plastic composite deck boards, stair treads, guards or handrails. Plastic composite exterior deck boards, stair treads, guards and handrails shall comply with the requirements of ASTM D7032 and this section.

R507.2.2.1 Labeling. Plastic composite deck boards and stair treads, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the allowable load and maximum allowable span determined in accordance with ASTM D7032. Plastic or composite handrails and guards, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the maximum allowable span determined in accordance with ASTM D7032.

R507.2.2.2 Flame spread index. Plastic composite deck boards, stair treads, guards, and handrails shall exhibit a flame spread index not exceeding 200 when tested in accordance with ASTM E84 or UL 723 with the test specimen remaining in place during the test.

Exception: Plastic composites determined to be noncombustible.

R507.2.2.3 Decay resistance. Plastic composite deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall be decay resistant in accordance with ASTM D7032.

R507.2.2.4 Termite resistance. Where required by Section 305, plastic composite deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall be termite resistant in accordance with ASTM D7032.

R507.2.2.5 Installation of plastic composites. Plastic composite deck boards, stair treads, guards and handrails shall be installed in accordance with this code and the manufacturer’s instructions.

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R507.2.3 Fasteners and connectors. Metal fasteners and connectors used for all decks shall be in accordance with Section R304.3 and Table R507.2.3. Holes for through bolts shall be drilled to a diameter of [1] / 32 inch to [1] / 16 inch larger than the bolt diameter. Connectors shall be installed in accordance with the manufacturer’s approved instructions.

|TABLE R507.2.3—FASTENER AND CONNECTOR SPECIFICATIONS FOR DECKSa,
CBC § 2.3 Medium relevance — show source text
SIP R610.8

Steel R603.6

Wood R602.7

Hearth R1001.9

Extension R1001.10, R1001.9

Heaters

Masonry R1002 Heating Required R325.8 Height Ceiling R313 Mezzanines R314.2 Sleeping lofts R315.3 Hollow-Unit Masonry (see Masonry)

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INDEX

Roof shingles R905.4 Methods Water distribution pipe sizing Appendix CF Mezzanines (see also Sleeping Lofts) R314, R321 Modifications R104.2.3 Moisture Content, Building Materials R109.1.4.1

Moisture Control R702.7

Mortar

Joints R606.3.1 Multiple Flues R1003.13

Natural Light (see Light) Natural Ventilation (see Ventilation) Notching Steel joists R505.2.5, R505.3.5, R804.2.5, R804.3.3 Steel studs R603.2.6, R603.3.4 Wood joists R502.8, R802.7.1 Wood studs R602.6 Wood top plates R602.6.1

Opening Protection R302.5

Parapets R302.2.2, R606.4.4 Particleboard

Floor R503.3

Walls R605 Patio Covers Appendix BF Penetrations R302.4, R302.5 Permits 1.8.4, R105, R105.5.1 Permit fees Appendix AB Photovoltaic Panel Systems R907 Ground-mounted definition R202

Photovoltaic Support Structure, Elevated R202, R324.8, R324.8.1, R324.8.2 Piers R606.7

Masonry R404.1.9 Planning Building Chapter 3 Plans R106

Plaster

Exterior R703.7

Interior R702.2

Platform Lifts R323.2, R323.3 Plumbing Fixture clearances R327

Fixtures R326, R327 Inspection 109.1.2 Requirements and definitions R202 System, definition R202 Plywood Application R703.5 Materials, walls R604

Precast Concrete

Footings R403.4 Foundation material R402.3.1

Foundation walls R404.5

Protection Against decay and termites R304, R305 Against radon Appendix BE Public Way R318.1, R319.1 Purlins R802.4.5

Hot Tubs (see Swimming Pools) R324.3.1, R328 Hurricane (see Storm Shelter)

Impact Protective System Energy storage system R330.8 Flood R306.1.4.2, R306.3.3 Human impact R324.3 Storm shelter R307.2.1
CBC § 2304.12.1.1.1 Medium relevance — show source text
2304.12.1.1.1 [SPCB] There shall be a clearance of at least 18 inches (457 mm) between the underside of wood floor joists and the finished surface of the ground, and at least 12 inches (305 mm) between the underside of any other wood horizontal framing member and the finished surface of the ground. The ground underneath floor joists shall be leveled or smoothed off so as to maintain a reasonably even surface.

Exception: For purposes of structural pest control inspection, a minimum of 12 inches (305 mm) of clearance under-floor joists shall be considered adequate except that such clearance shall not be necessary where the subarea soil is of such a nature as to prevent excavation or where excavation would create a hazard from shifting soil or other causes.

2304.12.1.2 Wood supported by exterior foundation walls. Wood framing members, including wood sheathing, that are in contact with exterior foundation walls and are less than 8 inches (203 mm) from exposed earth shall be of naturally durable or preservative-treated wood.

Exception: [DSA-SS and OSHPD 1, 1R, 2, 4 & 5] At exterior walls where the earth is paved with an asphalt or concrete slab at least 18 inches (457 mm) wide and draining away from the building, the bottom of sills are permitted to be 6 inches (152 mm) above the top of such slab. Other equivalent means of termite and decay protection may be accepted by the enforcement agency.

2304.12.1.3 Exterior walls below grade. Wood framing members and furring strips in direct contact with the interior of exterior masonry or concrete walls below grade shall be of naturally durable or preservative-treated wood.

2304.12.1.4 Sleepers and sills. Sleepers and sills on a concrete or masonry slab that is in direct contact with earth shall be of naturally durable or preservative-treated wood.

2304.12.1.4.1 Additional requirements. [DSA-SS and OSHPD 1, 1R, 2, 4 & 5] Stud walls or partitions at shower or toilet rooms with more than two plumbing fixtures, excluding floor drains, and stud walls adjacent to unroofed paved areas shall rest on a concrete curb extending at least 6 inches (152 mm) above finished floor and pavement level.

2304.12.1.5 Wood siding. Clearance between wood siding and earth on the exterior of a building shall be not less than 6 inches (152 mm) or less than 2 inches (51 mm) vertical from concrete steps, porch slabs, patio slabs and similar horizontal surfaces exposed to the weather except where siding, sheathing and wall framing are of naturally durable or preservativetreated wood.
CBC § 2308.10 Medium relevance — show source text
walls 2308.10 Calculated fire resistance 722.6 Ceiling framing 2308.11 Connectors and fasteners 2304.10,

2308.5

Contacting concrete, masonry or earth 2304.12.1.3, 2304.12.1.4, 2304.12.2.1, 2304.12.2.2, 2304.12.2.6 Cross-laminated timber 2301.2, 2303.1, 2303.1.4, 2304.11.2.1, 2304.11.3.1, 2304.11.4.1 Cutting, notching and boring of dimensional wood framing 2308.6 Decay, protection against 2304.12 Diaphragms 2305.1, 2305.2, 2306.2 Dimensions 2301.2 Draftstopping 718.3, 718.4 End-jointed lumber 2303.1.1.2 Fiberboard 2303.1.6, Table 2306.3(2) Fireblocking 718.2 Fire-retardant treated 2303.2 Floor and roof framing (see Floor Construction, Wood) 2304.4 Floor sheathing 2304.8 Foundation 1807.1.4, 2304.10.6.2, 2304.12.1.2, 2308.10.8.1, 2308.7 Grade, lumber 2303.1.1

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INDEX

Hardboard 2303.1.7 Heavy timber construction 602.4, 2304.11

Hurricane shutters 1609.2

I-joist 2303.1.2 Inspection, special 1705.12.1, 1705.13.2, 1705.5 Lateral force-resisting systems 2305 Light-frame construction, conventional 2308 Load and resistance factor design 2307

Moisture content 2303.1.9.2, 2303.2.9, 2303.7, 2304.9.5.1, Table 2305.2(1), Table 2305.2(2) Nails and staples 2303.6 Plywood, hardwood 2303.3 Preservative treated 1402.6, 1402.9,

2303.1.9 Roof framing (see Roof Construction, Wood)

2304.4 Roof sheathing 2304.8 Seismic provisions 2305, 2306, 2308.10.10, 2308.10.6, 2308.10.8 Shear walls 2305, 2306.3 Standards and quality, minimum 2303 Structural panels 2303.1.5 Supporting concrete or masonry 2304.13 Termite, protection against 2304.12 Trusses 2303.4

Veneer Chapter 14 Wall framing (see Wall, Wood Construction)

2304.3 Wall sheathing, exterior 2304.6 Wood Frame Construction Manual
CBC § 1404.15.1.1 Medium relevance — show source text
Nailable Substrate 1404.15.1.1, 1404.18.1,

1404.18.2 Nailing 2303.6, 2304, 2304.10, 2308.10.6.1 Naturally Durable Wood 2304.12 Nominal Loads 1604.2 Nominal Size (Lumber) 2301.2 Noncombustible Building Material 703.4 Noncombustible 202 Noncombustible protection for mass timber 602.4, 722.7 Nurses Stations (see Care Provider Stations) Nursing Homes

[see Institutional (Group I-2)] 308.3, 407

Occupancy Accessory 507.1.1, 508.2

Ceiling height 1003.2 Child care facilities (see Day Care) Configuration 1007 Construction drawings 107.2.3 Convergence 1005.6 Covered and open mall buildings 402.8 Day care facilities 308.5, 310.4.1, 1006.2.2.4

Distribution 1005.5

Doors 1005.7, 1006.2, 1010, 1022.2,

2702.2

During construction 3303.3, 3310 Elevation change 1003.5 Elevators 403.5.2, 403.6.2, 1003.7, 1009, 3008 Emergency escape and rescue 1031 Encroachment 1005.7 Equipment platform 505.3 Escalators 1003.7

Evacuation plans 1002.2 Existing buildings 3310 Exit (see Exit) 1022, 1027 Exit access (see Exit Access) 1016, 1021 Exit discharge (see Exit Discharge) 1028 Exit enclosures 1023.2

Exit passageway 1024 Exit signs 1013, 2702.2 Fire escapes 412.7.3 Fire safety plans 1002.2 Floor surface 804, 1003.4 Gates 1010.4

Group I-2 407.2, 407.3, 407.4, 1019.4 Group I-3 408.2, 408.3, 408.4, 408.6, 408.8, 1019.4 Guards 1015

Handrails 1014

Hazardous materials 414.6.1.2, 415.11.2, 415.11.6.6 Headroom 1003.2, 1003.3 Heliports, Helistops 412.7.3 High-hazard Group H 415.11.2 High-rise 403.5, 403.6 Illumination 1008, 2702.2 Interior finish 803.13, 804 Ladders (see Ladders) Live loads Table 1607.1

Live/work units 508.5.3 Mezzanines 505.2.2, 505.2.3, 1004.2.2,

CBC § 2304.8 Medium relevance — show source text

TABLE 2304.8(1)—ALLOWABLE SPANS FOR LUMBER FLOOR AND ROOF SHEATHING	Col2	Col3	Col4	Col5
SPAN (inches)	MINIMUM NET THICKNESS (inches) OF LUMBER PLACED	MINIMUM NET THICKNESS (inches) OF LUMBER PLACED	MINIMUM NET THICKNESS (inches) OF LUMBER PLACED	MINIMUM NET THICKNESS (inches) OF LUMBER PLACED
SPAN (inches)	Perpendicular to supports	Perpendicular to supports	Diagonally to supports	Diagonally to supports
SPAN (inches)	Surfaced drya	Surfaced unseasoned	Surfaced drya	Surfaced unseasoned
Floors	Floors	Floors	Floors	Floors
24	3/4	25/32	3/4	25/32
16	5/8	11/16	5/8	11/16
Roofs	Roofs	Roofs	Roofs	Roofs
24	5/8	11/16	3/4	25/32
For SI: 1 inch = 25.4 mm. a. Maximum 19-percent moisture content.	For SI: 1 inch = 25.4 mm. a. Maximum 19-percent moisture content.	For SI: 1 inch = 25.4 mm. a. Maximum 19-percent moisture content.	For SI: 1 inch = 25.4 mm. a. Maximum 19-percent moisture content.	For SI: 1 inch = 25.4 mm. a. Maximum 19-percent moisture content.

TABLE 2304.8(2)—SHEATHING LUMBER, MINIMUM GRADE REQUIREMENTS: BOARD GRADE	Col2	Col3
SOLID FLOOR OR ROOF SHEATHING	SPACED ROOF SHEATHING	GRADING RULES
Utility	Standard	NLGA, PLIB/WCLIB, or WWPA
4 common or utility	3 common or standard	NLGA, PLIB/WCLIB, WWPA, or NELMA
No. 3	No. 2	SPIB
Merchantable	Construction common	RIS

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|TABLE 2304.

CBC § 2301.2 Medium relevance — show source text
2301.2 Dimensions. For the purposes of this chapter, where dimensions of lumber are specified, they shall be deemed to be nominal dimensions unless specifically designated as actual dimensions (see Section 2304.2). Where dimensions of cross-laminated timber thickness are specified, they shall be deemed to be actual dimensions.

SECTION 2302—DESIGN REQUIREMENTS

2302.1 General. The design of structural elements or systems, constructed partially or wholly of wood or wood-based products, shall be in accordance with one of the following methods:
1. Allowable stress design in accordance with Sections 2304, 2305 and 2306.
2. Load and resistance factor design in accordance with Sections 2304, 2305 and 2307.
3. Conventional light-frame construction in accordance with Sections 2304 and 2308.
4. AWC WFCM in accordance with Section 2309.
5. The design and construction of log structures in accordance with the provisions of ICC 400.
SECTION 2303—MINIMUM STANDARDS AND QUALITY

2303.1 General. Structural sawn lumber; end-jointed lumber; prefabricated wood I-joists; structural glued-laminated timber; crosslaminated timber; wood structural panels; fiberboard sheathing (where used structurally); hardboard siding (where used structurally); particleboard; preservative-treated wood; structural log members; structural composite lumber; round timber poles and piles; fire-retardant-treated wood; hardwood plywood; wood trusses; joist hangers; nails; and staples shall conform to the applicable provisions of this section.

2303.1.1 Sawn lumber. Sawn lumber used for load-supporting purposes, including end-jointed or edge-glued lumber, machine stress-rated or machine-evaluated lumber, shall be identified by the grade mark of a lumber grading or inspection agency that has been approved by an accreditation body that complies with DOC PS 20 or equivalent. Grading practices and identification shall comply with rules published by an agency approved in accordance with the procedures of DOC PS 20 or equivalent procedures.

2303.1.1.1 Certificate of inspection. In lieu of a grade mark on the material, a certificate of inspection as to species and grade issued by a lumber grading or inspection agency meeting the requirements of this section is permitted to be accepted for precut, remanufactured or rough-sawn lumber and for sizes larger than 3 inches (76 mm) nominal thickness.

2303.1.1.2 End-jointed lumber. Approved end-jointed lumber is permitted to be used interchangeably with solid-sawn members of the same species and grade. End-jointed lumber used in an assembly required to have a fire-resistance rating shall have the designation “Heat Resistant Adhesive” or “HRA” included in its grade mark.

2303.1.2 Prefabricated wood I-joists. Structural capacities and design provisions for prefabricated wood I-joists shall be established and monitored in accordance with ASTM D5055.

2303.1.3 Structural glued-laminated timber. Glued-laminated timbers shall be manufactured and identified as required in ANSI/APA 190.1 and ASTM D3737.
CBC § 505.3.1 Medium relevance — show source text
505.3.1

Egress 505.2.2, 505.2.3, 1009.1 Equipment platforms 505.3 Guards 505.3.3, 1015.1 Height 505.2 Occupant load 1004.2.2 Stairways 712.1.11, 1011.14, 1019, 1023.2 Micropile 1810.3.10, Table 1810.3.2.6, 1810.3.5.2.3, 1810.4.10 Mirrors 1010.1, 2406.1 Mixed Occupancy (see Occupancy Separation) Modifications 104.2.4, 104.4 Modified Bitumen Roof Covering 1507.11 Moisture Protection 1210, 1402.2, 1503 Monasteries 310.3

Mortar 202

Ceramic tile 2103.2.3 Dampproofing 1805.2.2 Fire resistance 714.4.1, 715.5 Glass unit masonry 2110.1.1 Masonry 2103.2 Surface-bonding 2103.2.2 Motel 202

Motels 310.2, 310.3 Motion Picture Projection Rooms 409 Construction 409.2

Exhaust air 409.3.2, 409.3.3 Lighting control 409.4 Projection room 409.3 Supply air 409.3.1 Ventilation 409.3 Motor Fuel-Dispensing System 406.7 Accessibility Chapter 11B Motor Vehicle Facilities 304, 311, 406 Moving, Buildings 101.4.7, D103.3 Moving Walk 3004.2 Means Of Egress 1003.7

Nailable Substrate 1404.15.1.1, 1404.18.1,

1404.18.2 Nailing 2303.6, 2304, 2304.10, 2308.10.6.1 Naturally Durable Wood 2304.12 Nominal Loads 1604.2 Nominal Size (Lumber) 2301.2 Noncombustible Building Material 703.4 Noncombustible 202 Noncombustible protection for mass timber 602.4, 722.7 Nurses Stations (see Care Provider Stations) Nursing Homes

[see Institutional (Group I-2)] 308.3, 407

Occupancy Accessory 507.1.1, 508.2

Ceiling height 1003.2 Child care facilities (see Day Care) Configuration 1007 Construction drawings 107.2.3 Convergence 1005.6 Covered and open mall buildings 402.8 Day care facilities 308.5, 310.4.1, 1006.2.2.4

Distribution 1005.5

Doors 1005.7, 1006.2, 1010, 1022.2,

2702.2
CBC § 2301.1.5 Medium relevance — show source text
2301.1.5 Prohibition. [DSA-SS & DSA-SS/CC & OSHPD 1, 1R, 2, 4 & 5] The following design methods, systems and materials are not permitted by DSA and OSHPD: 1. Straight-sheathed horizontal lumber diaphragms. 2. Gypsum-based sheathing shear walls and portland cement plaster shear walls. 3. Shear wall foundation anchor bolt washers in accordance with exception to AWC SDPWS Section 4.3.6.4.3.

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WOOD

4. Wood structural panel shear walls and diaphragms using staples as fasteners.

5. Unblocked shear walls.

6. Any wood structural panel sheathing used for diaphragms and shear walls that are part of the seismic force-resisting system, not applied directly to framing members. 7. Single and double diagonally sheathed lumber walls used to resist seismic forces. 8. Log structures in accordance with ICC 400. 9. [OSHPD 1, 1R, 2, 4 & 5] Cross-laminated timber used as part of the seismic force-resisting system, unless approved as an alternative system in accordance with Section 104.2.3. [DSA-SS, DSA-SS/CC] Not adopted by DSA.

2301.2 Dimensions. For the purposes of this chapter, where dimensions of lumber are specified, they shall be deemed to be nominal dimensions unless specifically designated as actual dimensions (see Section 2304.2). Where dimensions of cross-laminated timber thickness are specified, they shall be deemed to be actual dimensions.

SECTION 2302—DESIGN REQUIREMENTS

2302.1 General. The design of structural elements or systems, constructed partially or wholly of wood or wood-based products, shall be in accordance with one of the following methods:
1. Allowable stress design in accordance with Sections 2304, 2305 and 2306.
2. Load and resistance factor design in accordance with Sections 2304, 2305 and 2307.
3. Conventional light-frame construction in accordance with Sections 2304 and 2308.
4. AWC WFCM in accordance with Section 2309.
5. The design and construction of log structures in accordance with the provisions of ICC 400.
SECTION 2303—MINIMUM STANDARDS AND QUALITY

2303.1 General. Structural sawn lumber; end-jointed lumber; prefabricated wood I-joists; structural glued-laminated timber; crosslaminated timber; wood structural panels; fiberboard sheathing (where used structurally); hardboard siding (where used structurally); particleboard; preservative-treated wood; structural log members; structural composite lumber; round timber poles and piles; fire-retardant-treated wood; hardwood plywood; wood trusses; joist hangers; nails; and staples shall conform to the applicable provisions of this section.
CBC § 2.25 Medium relevance — show source text
00|2.25|0.70|DR|3.70|1.05|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|33 mil cold-
formed steel
stud|#10 screw|Steel thick-
ness plus 3
threads|16|3.85|1.45|DR|DR|3.40|DR|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|33 mil cold-
formed steel
stud|#10 screw|Steel thick-
ness plus 3
threads|24|3.40|DR|DR|DR|2.70|DR|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|43 mil or
thicker cold-
formed steel
stud|#8 Screw|Steel thick-
ness plus 3
threads|12|3.00|1.80|DR|DR|3.00|0.65|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|43 mil or
thicker cold-
formed steel
stud|#8 Screw|Steel thick-
ness plus 3
threads|16|3.00|1.00|DR|DR|2.85|DR|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|43 mil or
thicker cold-
formed steel
stud|#8 Screw|Steel thick-
ness plus 3
threads|24|2.85|DR|DR|DR|2.20|DR|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|43 mil or
thicker cold-
formed steel
stud|#10 screw|Steel thick-
ness plus 3
threads|12|4.00|3.85|2.80|1.80|4.00|3.05|1.50|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|43 mil or
thicker cold-
formed steel
stud|#10 screw|Steel thick-
ness plus 3
threads|16|4.00|3.30|1.95|0.60|4.00|2.25|DR|DR| |Minimum 33
mil steel
furring or
minimum
1x wood
furringc|43 mil or
thicker cold-
formed steel
stud|#10 screw|Steel thick-
ness plus 3
threads|24|4.00|2.25|DR|DR|4.00|0.65|DR|DR| |For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
DR = Design Required, o.c. = on center.
a. Wood furring shall be spruce-pine-fir or any softwood species with a specific gravity of 0.42 or greater.
CBC § 4.00 Medium relevance — show source text
10
wood screw|1|24|4.00|0.90|DR|DR|2.85|DR|DR|DR| |Minimum 1x
Wood Furringd|Minimum 2x
Wood Stud|1/4" lag screw|11/2|12|4.00|2.65|1.50|0.90|4.00|1.65|0.80|DR| |Minimum 1x
Wood Furringd|Minimum 2x
Wood Stud|1/4" lag screw|11/2|16|4.00|1.95|0.95|0.50|4.00|1.10|DR|DR| |Minimum 1x
Wood Furringd|Minimum 2x
Wood Stud|1/4" lag screw|11/2|24|4.00|1.10|DR|DR|3.25|0.50|DR|DR| |For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
DR = Design Required, o.c. = on center.
a. Wood framing and furring shall be spruce-pine-fir or any wood species with a specific gravity of 0.42 or greater in accordance with ANSI/AWC NDS.
b. Nail fasteners shall comply with ASTM F1667, except nail length shall be permitted to exceed ASTM F1667 standard lengths.
c. The thickness of wood structural panels complying with the specific gravity requirements of Note a shall be permitted to be included in satisfying the minimum required
penetration into framing.
d. Where the required cladding fastener penetration into wood material exceeds3/4 inch and is not more than 11/2 inches, a minimum 2-inch nominal wood furring or an
approved design shall be used.
e. Foam sheathing shall have a minimum compressive strength of 15 psi in accordance with ASTM C578 or ASTM C1289.
f. Furring shall be spaced not greater than 24 inches on center in a vertical or horizontal orientation. In a vertical orientation, furring shall be located over wall studs and attached with
the required fastener spacing. In a horizontal orientation, the indicated 8-inch and 12-inch fastener spacing in furring shall be achieved by use of two fasteners into studs at 16 inches
and 24 inches on center, respectively.|For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
DR = Design Required, o.c. = on center.
a. Wood framing and furring shall be spruce-pine-fir or any wood species with a specific gravity of 0.42 or greater in accordance with ANSI/AWC NDS.
b. Nail fasteners shall comply with ASTM F1667, except nail length shall be permitted to exceed ASTM F1667 standard lengths.
c. The thickness of wood structural panels complying with the specific gravity requirements of Note a shall be permitted to be included in satisfying the minimum required
penetration into framing.
d. Where the required cladding fastener penetration into wood material exceeds3/4 inch and is not more than 11/2 inches, a minimum 2-inch nominal wood furring or an
approved design shall be used.
e.

California Building Code Medium relevance — show source text

000|32,500|37,500|77,500|32,500|42,500|41,500|77,500| |Sheathing|24/16|27,000|35,000|40,500|83,500|35,000|45,500|44,500|83,500| |Sheathing|32/16|27,000|35,000|40,500|83,500|35,000|45,500|44,500|83,500| |Sheathing|40/20|28,500|37,000|43,000|88,500|37,000|48,000|47,500|88,500| |Sheathing|48/24|31,000|40,500|46,500|96,000|40,500|52,500|51,000|96,000| |Single
Floor|16 o.c.|27,000|35,000|40,500|83,500|35,000|45,500|44,500|83,500| |Single
Floor|20 o.c.|28,000|36,500|42,000|87,000|36,500|47,500|46,000|87,000| |Single
Floor|24 o.c.|30,000|39,000|45,000|93,000|39,000|50,500|49,500|93,000| |Single
Floor|32 o.c.|36,000|47,000|54,000|110,000|47,000|61,000|59,500|110,000| |Single
Floor|48 o.c.|50,500|65,500|76,000|155,000|65,500|85,000|83,500|155,000|

Col1	Col2	Structural Sheathing	Col4	Col5	Structural I	Col7	Col8
	Thickness (in.)	A-A, A-C	Marine	All Other Grades	A-A, A-C	Marine	All Other Grades
Sanded Plywood	1/4	24,000	31,000	24,000	31,000	31,000	31,000
Sanded Plywood	11/32	25,500	33,000	25,500	33,000	33,000	33,000
Sanded Plywood	3/8	26,000	34,000	26,000	34,000	34,000	34,000
Sanded Plywood	15/32	38,000	49,500	38,000	49,500	49,500	49,500
Sanded Plywood	1/2	38,500	50,000	38,500	50,000	50,000	50,000
Sanded Plywood	19/32	49,000	63,500	49,000	63,500	63,500	63,500
Sanded Plywood	5/8	49,500	64,500	49,500	64,500	64,500	64,500
Sanded Plywood— continued	23/32	50,500	65,500	50,

CBC § 2308.11.11. Medium relevance — show source text
Random
layup is permitted in accordance with the provisions of Section 2308.11.11. Lumber thickness is 11/2 inches nominal.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kN/m2, 1 pound per square inch = 0.00689 N/mm2.
a. Spans are based on simple beam action with 10 pounds per square foot dead load and provisions for a 300-pound concentrated load on a 12-inch width of decking. Random
layup is permitted in accordance with the provisions of Section 2308.11.11. Lumber thickness is 11/2 inches nominal.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kN/m2, 1 pound per square inch = 0.00689 N/mm2.
a. Spans are based on simple beam action with 10 pounds per square foot dead load and provisions for a 300-pound concentrated load on a 12-inch width of decking. Random
layup is permitted in accordance with the provisions of Section 2308.11.11. Lumber thickness is 11/2 inches nominal.|

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2308.11.12 Wood trusses. Wood trusses shall be designed in accordance with Section 2303.4. Connection to braced wall lines shall be in accordance with Section 2308.10.7.2.

2308.11.13 Attic ventilation. For attic ventilation, see Section 1202.2.1.

SECTION 2309—WOOD FRAME CONSTRUCTION MANUAL

2309.1 Wood Frame Construction Manual. Structural design in accordance with the AWC WFCM shall be permitted for buildings assigned to Risk Category I or II subject to the limitations of Section 1.1.3 of the AWC WFCM and the load assumptions contained therein. Structural elements beyond these limitations shall be designed in accordance with accepted engineering practice.

2309.1.1 Additional requirements. [DSA-SS, DSA-SS/CC, OSHPD 1R, 2 & 5] The use of the AWC WFCM is permitted provided the design and construction also comply with Sections 2304, 2305 and 2302.1, Item 1 or 2, and engineering analysis is furnished demon- strating compliance.

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CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

CHAPTER 24 – GLASS AND GLAZING

(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CBC § 2404.1 Medium relevance — show source text
Vertical 2404.1 Walkways 2409.1 Grade (Adjacent Ground Elevation) 202 Grading Appendix J Grain Elevators 426.1.5

Historic buildings G106.3 Interior finishes 802.4

Manufactured homes G109

Modifications 104.2.4.1

Recreation vehicles G110

Site improvements G108 Site plan 107.2.6 Subdivisions G107

Tank G111

Temporary G113 Utility G114 Floodway Appendix G, 1612.3 Floor Construction (see Floor Construction, Wood) Draftstopping 718.3 Finishes 804, 805, 1003.4, 1209.1 Fire resistance Table 601, 711 Loads (see Floor Loads) Materials Chapter 6 Penetration of fire-resistant

assemblies 711, 714.5, 717.2, 717.6 Pipes and trenches 1809.15 Floor Construction, Wood Beams and girders 2304.12.1.1, 2308.8.1 Bridging/blocking 2308.8.6, 2308.11.7 Diaphragms 2305.1 Fastening schedule 2304.10.2 Framing 2304.4, 2304.11.1.2, 2304.11.3, Table 2304.11, 2308.8 Joists 2308.8.2 Sheathing 2304.8 Floor Level 1003.5, 1010.1.4 Floor Loads

Construction documents 107.2

Live 1603.1.1, 1607 Posting 106.1 Floor Opening Protection (see Vertical Opening Protection) Floor/Ceiling (see Floor Construction) Foam Plastics

Attics 720.1, 2603.4.1.6 Cladding attachment 1404.5.1, 1404.5.2, 1404.5.3 Cold storage 2603.3, 2603.4.1.2, 2603.5

Concealed 603 Covered mall and open mall buildings 402.6.2, 402.6.4.5 Crawl space 2603.4.1.6 Doors 2603.4.1.7, 2603.4.1.9 Exterior wall covering 806.6.1, Chapter 14 Exterior walls of multistory buildings 1403.12, 2603.5 Interior finish 2603.9, 2604 Label/identification 2603.2 Metal composite material (MCM) 1406.12

Plenums 2603.7, 2604.1.1 Roofing 2603.4.1.5 Siding backer board 2603.4.1.10 Stages and platform scenery 410.2.6 Surface burning characteristics 2603.3 Termites, protection from 2603.8 Thermal barrier requirements 2603.5.2

Trim 806.6.1, 2604.2 Type I and II construction 603.1

Walk-in coolers 2603.4.1.3
CBC § 3.4. Medium relevance — show source text
[BS] ROOF COATING. A fluid-applied adhered coating used for roof maintenance, roof repair or as a component of a roof covering system or roof assembly.

[BS] ROOF RECOVER. The process of installing an additional roof covering over a prepared existing roof covering without removing the existing roof covering.

[BS] ROOF REPAIR. Reconstruction or renewal of any part of an existing roof for the purpose of correcting damage or restoring the predamage condition.

[BS] ROOF REPLACEMENT. The process of removing the existing roof covering, repairing any damaged substrate and installing a new roof covering.

SPC SEISMIC SEPARATION. [OSHPD 1 & 1R] Means a building separation in accordance with the California Administrative Code, Chap- ter 6 Section 3.4.

SUBSTANDARD BUILDING. [HCD 1, HCD 2] See Health and Safety Code Section 17920.3.

[BG] STORM SHELTER. A building, structure or portions thereof, constructed in accordance with ICC 500, designated for use during hurricanes, tornadoes or other severe windstorms.

[BS] SUBSTANTIAL DAMAGE. For the purpose of determining compliance with the flood provisions of this code, damage of any origin sustained by a structure whereby the cost of restoring the structure to its before-damaged condition would equal or exceed 50 percent of the market value of the structure before the damage occurred.

[BS] SUBSTANTIAL IMPROVEMENT. For the purpose of determining compliance with the flood provisions of this code, any repair, alteration, addition or improvement of a building or structure, the cost of which equals or exceeds 50 percent of the market value of the structure, before the improvement or repair is started. If the structure has sustained substantial damage, any repairs are considered substantial improvement regardless of the actual repair work performed. The term does not, however, include either of the following:
1. Any project for improvement of a building required to correct existing health, sanitary or safety code violations identified by the code official and that is the minimum necessary to ensure safe living conditions.
2. Any alteration of a historic structure, provided that the alteration will not preclude the structure’s continued designation as a historic structure.
[BS] SUBSTANTIAL STRUCTURAL ALTERATION. An alteration in which the gravity load-carrying structural elements altered within a 5-year period support more than 30 percent of the total floor and roof area of the building or structure. The areas to be counted toward the 30 percent shall include mezzanines, penthouses, and in-filled courts and shafts tributary to the altered structural elements.

[BS] SUBSTANTIAL STRUCTURAL DAMAGE. A condition where any of the following apply:
1. The vertical elements of the lateral force-resisting system have suffered damage such that the lateral load-carrying capacity of any story in any horizontal direction has been reduced by more than 33 percent from its predamage condition.
2. The capacity of any vertical component carrying gravity load, or any group of such components, that has a tributary area more than 30 percent of the total area of the structure’s floor(s) and roof(s) has been reduced more than 20 percent from its predamage condition, and the remaining capacity of such affected elements, with respect to all dead and live loads, is less than 75 percent of that required by the California Building Code for new buildings of similar structure, purpose and location.
CBC § 3.6 Medium relevance — show source text
Staples used for framing and sheathing connections shall have minimum average bending moments as follows: 3.6 in.-lbs (0.41 N-m) for No. 16 gage staples, 4.0 in.-lbs (0.45 N-m) for No. 15 gage staples, and 4.3 in.-lbs (0.49 N-m) for No. 14 gage staples.

2303.7 Shrinkage. Consideration shall be given in design for the effects of wood cross-grain dimensional changes that occur as a result of changes in the wood moisture content after installation.

2025 CALIFORNIA BUILDING CODE 23-11

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WOOD

SECTION 2304—GENERAL CONSTRUCTION REQUIREMENTS

2304.1 General. The provisions of this section apply to design methods specified in Section 2302.1.

2304.2 Size of structural members. Computations to determine the required sizes of members shall be based on the net dimensions (actual sizes) and not nominal sizes.

2304.3 Wall framing. The framing of exterior and interior walls shall be in accordance with the provisions specified in Section 2308 unless a specific design is furnished. 2304.3.1 Bottom plates. Studs shall have full bearing on a 2-inch-thick (actual 1 [1] / 2 -inch, 38 mm) or larger plate or sill having a width not less than equal to the width of the studs.

2304.3.1.1 [HCD 1] Rodent proofing. Annular spaces around pipes, electric cables, conduits or other openings in bottom/sole plates at exterior walls shall be protected against the passage of rodents by closing such openings in accordance with the Califor- nia Green Building Standards Code (CALGreen), Chapter 4, Division 4.4.

2304.3.2 Framing over openings. Headers, double joists, trusses or other approved assemblies that are of adequate size to transfer loads to the vertical members shall be provided over window and door openings in load-bearing walls and partitions.

2304.3.3 Shrinkage. Wood walls and bearing partitions shall not support more than two floors and a roof unless an analysis satisfactory to the building official shows that shrinkage of the wood framing will not have adverse effects on the structure or any plumbing, electrical or mechanical systems or other equipment installed therein due to excessive shrinkage or differential movements caused by shrinkage. The analysis shall show that the roof drainage system and the foregoing systems or equipment will not be adversely affected or, as an alternate, such systems shall be designed to accommodate the differential shrinkage or movements.

2304.3.4 Additional requirements. [DSA-SS, DSA-SS/CC and OSHPD 1, 1R, 2, 4 & 5] The following additional requirements apply: 1. Engineering analysis shall be furnished that demonstrates compliance of wall framing elements and connections with Section 2302.1, Item 1 or 2.

2. Construction documents shall include detailing of sill plate anchorage to supporting masonry or concrete for all exterior _and interior bearing, nonbearing and shear walls.

Frequently asked questions

Do I always have to use pressure‑treated wood near foundations?

If the wood location meets the CBC thresholds (for example, joists < 18 in. from exposed ground or wood framing < 8 in. from exposed earth at exterior foundation walls), the CBC requires either naturally durable wood or preservative‑treated wood for that location per § 2304.12.1.1 and § 2304.12.1.2 .

Is a concrete slab next to a sill always an automatic exception?

No. The exception that allows sills 6 in. above a slab applies only where the slab is at least 18 in. wide and drains away from the building; otherwise the 8‑inch clearance or treated/naturally durable wood requirement applies (§ 2304.12.1.2).

What standard defines acceptable preservative treatments?

The CBC references AWPA U1 (and AWPA end‑use designations) for waterborne and soil/freshwater treatments; use products and markings that comply with AWPA and the manufacturer’s instructions as applicable (see §§ 2304.12.1 and 2304.12.2.6).

If I buy preservative‑treated lumber, do I need to retreat any field cuts?

Yes; field‑cut ends, notches and drilled holes on preservative‑treated wood should be field‑treated consistent with industry standards (AWPA M4 is referenced in the Residential Code for dwellings). Check the project scope to determine the correct standard and marking requirements.

Where can I propose an alternative to treated wood?

The CBC allows the enforcement agency (building official) to accept other equivalent methods of termite and decay protection at their discretion; provide documentation and an approved alternative protection method for review (see exceptions / agency acceptance language in § 2304.12.1.2).

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Related in the CBC

Sheathing, decking and panel application requirements (nailing, span, orientation)

Fasteners, connectors and corrosion requirements for treated and exterior wood

Construction Practices & Fastening

California Building Code