CEBC · California Existing Building Code
Are storm shelter provisions applicable to my project?
If you’re adding to a school (Group E) and the addition will hold 50 or more people in an area where the ICC 500 tornado-shelter wind-speed map shows **250 mph**, the CEBC **§ 303.2** requires a storm shelter built to ICC 500 (and CBC § 423) sized for the site’s design occupant capacity unless an exception applies.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
The California Existing Building Code requires that storm shelters constructed for protection from tornadoes, hurricanes and other severe windstorms comply with the standards referenced in § 303.1 and be built in accordance with Section 423 of the California Building Code and ICC 500. § 303.2 specifically requires a storm shelter when an addition to a Group E occupancy is located in an area where the shelter design wind speed for tornadoes is 250 mph and the addition’s occupant load is 50 or more.
If you are adding to a school (Group E) in an area where the tornado shelter design wind speed is 250 mph and the addition will hold 50 or more people, provide a storm shelter designed to ICC 500.
Requirements in detail
Scope and construction standard
- The CEBC § 303.1 defines the section scope: it applies to design and construction of storm shelters for tornadoes, hurricanes and other severe windstorms. § 303.1.1 requires construction in accordance with Section 423 of the California Building Code and ICC 500; shelters must be designated as hurricane, tornado, or combined hurricane/tornado shelters.
When CEBC requires a shelter (the primary trigger)
- The mandatory trigger in the CEBC is for additions to existing Group E occupancies in high-design-wind areas:
- Where the shelter design wind speed for tornadoes (per ICC 500 Figure 304.2(1)) is 250 mph, and
- The occupant load in the addition is 50 or more,
then the addition must have a storm shelter constructed in accordance with ICC 500 (CEBC § 303.2).
How to calculate required shelter capacity
- Design occupant capacity must include all buildings on the site — the total occupant load of classrooms, vocational rooms and offices in the Group E occupancy — unless one of the CEBC exceptions applies (see next section). This is set out in § 303.2.1.
Location / travel distance
- The CEBC references CBC storm-shelter location rules; CBC § 423.4.2 and § 423.5.2 normally limit travel distance to 1,000 feet (305 m) from an exterior door of the building to the shelter door, but CEBC § 303.1.1 provides an exception for storm shelters added to critical emergency operations facilities or Group E occupancies (i.e., those additions are not required to meet CBC travel-distance provisions). See CBC Section 423 for the detailed locational rules.
Decision table — Which projects trigger CEBC storm-shelter requirements
| Decision dimension | Trigger / value (decision-relevant) | Required action under CEBC | Code Reference |
|---|---|---|---|
| Project type | Addition to existing building | Evaluate storm-shelter triggers in § 303.2 | § 303.2 |
| Occupancy | Group E (schools, instructional) | If addition is Group E, apply § 303.2 rules | § 303.2 |
| Tornado design wind speed | 250 mph (per ICC 500 Figure 304.2(1)) | If site is in this wind-speed area, CEBC trigger applies | § 303.2 |
| Addition occupant load | 50 or more occupants in the addition | Storm shelter required per ICC 500 | § 303.2 |
| Shelter capacity | Required capacity = total occupant load of all buildings on site (classrooms, vocational rooms, offices) | Construct shelter sized to that design occupant capacity (with listed exceptions) | § 303.2.1 |
| Construction standard | NA | Shelter must comply with ICC 500 and CBC § 423 requirements | § 303.1.1 |
| Travel distance | Normally ≤ 1,000 ft from exterior door to shelter door | CBC § 423 travel-distance rule applies unless exception in CEBC § 303.1.1 | CBC § 423.4.2 / § 423.5.2; see § 303.1.1 |
Exceptions & special cases
- CEBC lists three explicit exceptions to the Group E addition trigger in § 303.2:
- Group E day care facilities (no shelter requirement under this trigger).
- Group E occupancies accessory to places of religious worship.
- Additions meeting the requirements for shelter design in ICC 500 (i.e., if the addition itself meets ICC 500 shelter design, the CEBC addition trigger is satisfied).
- For design occupant capacity, CEBC § 303.2.1 includes two common reductions (exceptions):
- If the addition cannot physically accommodate the full site requirement, the shelter must at least accommodate the addition’s required capacity; and
- With building official approval, the required capacity may be reduced by the capacity of any existing storm shelters on-site.
- CEBC § 303.1.1 provides that storm shelters added to critical emergency operations facilities or Group E occupancies are not required to comply with the CBC travel-distance rules (CBC § 423.4.2 / § 423.5.2). That is a limited travel-distance exception; other CBC requirements (ICC 500 compliance, risk-category designations) still apply.
Common mistakes
- Assuming storm-shelter rules apply only to new detached shelters — CEBC applies the trigger to additions to Group E per § 303.2 (not only to new standalone shelters).
- Forgetting the 250 mph wind-speed threshold — the CEBC trigger is tied to the ICC 500 tornado-shelter design-wind map; confirm the site’s ICC 500 Figure 304.2(1) wind-speed zone. Do not assume uniform statewide applicability.
- Calculating required shelter capacity using only the addition’s occupant load instead of the required design occupant capacity (which generally includes all buildings on the site) unless you qualify for one of the § 303.2.1 exceptions.
- Overlooking that CEBC defers technical design details to ICC 500 and CBC § 423 — you still must provide sealed design documentation where required and follow ICC 500 structural and impact-protective requirements.
Worked example
Scenario: You are adding a classroom wing to an existing public elementary school (a Group E occupancy). The addition will hold 60 students/staff (occupant load = 60). The project site is located in an area where ICC 500 Figure 304.2(1) shows a 250 mph shelter-design wind speed.
- Does CEBC require a storm shelter?
- Yes. The project is an addition to a Group E occupancy, in a 250 mph wind-speed area, and the addition’s occupant load is 50 or more, so § 303.2 applies and a storm shelter constructed per ICC 500 is required.
- How large must the shelter be?
- Per § 303.2.1, the required design occupant capacity generally includes all buildings on the site (total occupant load of classrooms, vocational rooms and offices). If the existing school and addition together have, say, 300 total occupants, the shelter must be sized for 300 persons (unless an exception applies).
- Are there any exception pathways?
- If the addition cannot physically accommodate the shelter for the entire site, CEBC allows (by exception) the shelter to at minimum accommodate the addition’s required capacity (i.e., 60). Alternatively, with the code official’s approval, the required capacity can be reduced by the capacity of any existing on-site storm shelters. See § 303.2.1.
- Which technical standard governs the design?
- Design and construction must follow ICC 500 and CBC Section 423 (structural/occupancy classification, location, etc.). Expect to submit sealed design drawings showing ICC 500 compliance.
Related provisions
- § 302.5 (Occupancy and use — determines applicable referenced sections per building occupancy).
- § 304 (Structural design loads and evaluation procedures — structural evaluation guidance referenced by Chapter 3).
- § 317 (Earthquake evaluation and retrofit applicability — may be relevant to structural modifications when adding shelters or additions).
- California Building Code — Section 423 (Storm shelters: construction, occupancy classification, capacity and location requirements referenced from CEBC § 303.1.1). Note: Section 423 is in the CBC; CEBC defers technical design to it and to ICC 500.
Code references
Grounded in the retrieved California Existing Building Code — click a citation to read the verbatim passage:
CEBC § 302.5 High relevance — show source text
302.5 Occupancy and use. Where determining the appropriate application of the referenced sections of this code, the occupancy and use of a building shall be determined in accordance with Chapter 3 of the California Building Code .
SECTION 303—STORM SHELTERS
303.1 General. This section applies to the design and construction of storm shelters for the purpose of providing protection during tornadoes, hurricanes and other severe windstorms.
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303.1.1 Construction. Storm shelters shall be constructed in accordance with Section 423 of the California Building Code and ICC 500 and shall be designated as hurricane shelters, tornado shelters or combined hurricane and tornado shelters.
Exception: Storm shelters added to critical emergency operations facilities or Group E occupancies are not required to comply with the travel distance in Section 423.4.2 or 423.5.2 of the California Building Code .
303.2 Addition to a Group E occupancy. Where an addition is added to an existing Group E occupancy located in an area where the shelter design wind speed for tornadoes is 250 mph (402.3 km/h) in accordance with Figure 304.2(1) of ICC 500 and the occupant load in the addition is 50 or more, the addition shall have a storm shelter constructed in accordance with ICC 500.
Exceptions:
- Group E day care facilities.
- Group E occupancies accessory to places of religious worship.
- Additions meeting the requirements for shelter design in ICC 500.
303.2.1 Design occupant capacity. The required design occupant capacity of the storm shelter shall include all buildings on the site, and shall be the total occupant load of the classrooms, vocational rooms and offices in the Group E occupancy.
Exceptions:
- Where an addition is being added on an existing Group E site, and where the addition is not of sufficient size to accommodate the required occupant capacity of the storm shelter for all of the buildings on-site, the storm shelter shall at a minimum accommodate the required capacity for the addition.
- Where approved by the code official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
303.3 Occupancy classification. The occupancy classification for storm shelters shall be determined in accordance with Section 423.3 of the California Building Code .
SECTION 304—STRUCTURAL DESIGN LOADS AND EVALUATION AND DESIGN PROCEDURES
[BS] 304.1 Live loads. Where an addition or alteration does not result in increased design live load, existing gravity load-carrying structural elements shall be permitted to be evaluated and designed for live loads approved prior to the addition or alteration. If the approved live load is less than that required by Section 1607 of the California Building Code, the area designated for the nonconforming live load shall be posted with placards of approved design indicating the approved live load. Where the addition or alteration results in increased design live load, the live load required by Section 1607 of the California Building Code shall be used.
[BS] 304.2 Snow loads on adjacent buildings. Where an alteration or addition changes the potential snow drift effects on an adjacent building, the code official is authorized to enforce Section 7.12 of ASCE 7.
CEBC § 302.3 High relevance — show source text
302.3 Existing materials. Materials already in use in a building in compliance with requirements or approvals in effect at the time of their erection or installation shall be permitted to remain in use unless determined by the code official to be unsafe.
302.4 New and replacement materials. Except as otherwise required or permitted by this code, materials permitted by the applicable code for new construction shall be used. Like materials shall be permitted for repairs and alterations, provided that unsafe conditions are not created. Hazardous materials shall not be used where the code for new construction would not permit their use in buildings of similar occupancy, purpose and location. [HCD 1] Local ordinances or regulations shall permit the replacement, retention and extension of original materials, and the use of original methods of construction, for any building or accessory structure, provided such building or structure complied with the building code provisions in effect at the time of original construction and the building or accessory structure does not become or continue to be a substandard building. For additional information, see Health and Safety Code Sections 17912, 17920.3, 17922(d), 17922.3, 17958.8 and 17958.9.
Exception: No replacement residential garage door shall be installed to connect the replacement door to an existing residential automatic garage door opener that does not have a battery backup function designed to keep the garage door operational without interruption during an electrical outage. See Health and Safety Code Section 19892.
[BS] 302.4.1 New structural members and connections. New structural members and connections shall comply with the detailing provisions of the California Building Code for new buildings of similar structure, purpose and location.
Exception: Where alternative design criteria are specifically permitted.
302.5 Occupancy and use. Where determining the appropriate application of the referenced sections of this code, the occupancy and use of a building shall be determined in accordance with Chapter 3 of the California Building Code .
SECTION 303—STORM SHELTERS
303.1 General. This section applies to the design and construction of storm shelters for the purpose of providing protection during tornadoes, hurricanes and other severe windstorms.
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303.1.1 Construction. Storm shelters shall be constructed in accordance with Section 423 of the California Building Code and ICC 500 and shall be designated as hurricane shelters, tornado shelters or combined hurricane and tornado shelters.
Exception: Storm shelters added to critical emergency operations facilities or Group E occupancies are not required to comply with the travel distance in Section 423.4.2 or 423.5.2 of the California Building Code .
303.2 Addition to a Group E occupancy. Where an addition is added to an existing Group E occupancy located in an area where the shelter design wind speed for tornadoes is 250 mph (402.3 km/h) in accordance with Figure 304.2(1) of ICC 500 and the occupant load in the addition is 50 or more, the addition shall have a storm shelter constructed in accordance with ICC 500.
Exceptions:
- Group E day care facilities.
- Group E occupancies accessory to places of religious worship.
- Additions meeting the requirements for shelter design in ICC 500.
CEBC § 423.3.2 High relevance — show source text
- The occupancy category for a dedicated residential storm shelter shall be the Group R occupancy served.
423.3.2 Storm shelters within host buildings. Where designated storm shelters are constructed as a room or space within a host building that will normally be occupied for other purposes, the requirements of this code for the occupancy of the building, or the individual rooms or spaces thereof, shall apply unless otherwise required by ICC 500.
423.4 Critical emergency operations. In areas where the shelter design wind speed for tornados in accordance with Figure 304.2(1) of ICC 500 is 250 mph, 911 call stations, emergency operation centers and fire, rescue, ambulance and police stations shall comply with Table 1604.5 as a Risk Category IV structure and shall be provided with a storm shelter constructed in accordance with ICC 500.
423.4.1 Design occupant capacity. The required design occupant capacity of the storm shelter shall include the critical emergency operations on the site and shall be the total occupant load of offices and the number of beds.
Exceptions:
- Where approved by the building official, the actual number of occupants for whom each occupied space, floor or building is designed, although less than that determined by occupant load calculation, shall be permitted to be used in the determination of the required design occupant capacity for the storm shelter.
- Where a new building is being added on an existing site, and where the new building is not of sufficient size to accommodate the required design occupant capacity of the storm shelter for all of the buildings on the site, the storm shelter shall accommodate not less than the required occupant capacity of the new building.
- Where approved by the building official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
423.4.2 Location. Storm shelters shall be located within the building they serve or shall be located where the distance of travel from not fewer than one exterior door of each building to a door of the shelter serving that building does not exceed 1,000 feet (305 m), unless otherwise approved.
423.5 Group E occupancies. In areas where the shelter design wind speed for tornados is 250 mph in accordance with Figure 304.2(1) of ICC 500, all Group E occupancies with an occupant load of 50 or more shall have a storm shelter constructed in accordance with ICC 500.
Exceptions:
- Group E day care facilities.
- Group E occupancies accessory to places of religious worship.
- Buildings meeting the requirements for shelter design in ICC 500.
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SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE
423.5.1 Design occupant capacity. The required design occupant capacity of the storm shelter shall include all of the buildings on the site and shall be the total occupant load of the classrooms, vocational rooms and offices in the Group E occupancy.
Exceptions:
- Where approved by the building official, the actual number of occupants for whom each occupied space, floor or building is designed, although less than that determined by occupant load calculation, shall be permitted to be used in the determination of the required design occupant capacity for the storm shelter.
CEBC § 422.3.4 High relevance — show source text
422.3.4 Distance of travel. The distance of travel between any point in an ambulatory care facility and an exit shall be not greater than 200 feet (60 960 mm).
[F] 422.4 Automatic sprinkler systems. Automatic sprinkler systems shall be provided for ambulatory care facilities in accordance with Section 903.2.2.
[F] 422.5 Fire alarm systems. A fire alarm system shall be provided for ambulatory care facilities in accordance with Section 907.2.2.
[F] 422.6 Electrical systems. In ambulatory care facilities, the essential electrical system for electrical components, equipment and systems shall be designed and constructed in accordance with the provisions of Chapter 27 and California Electrical Code Article 517.
422.7 Domestic cooking. In fully sprinklered buildings, the installation of cooking appliances used in domestic cooking facilities shall comply with all of the following:
- The types of cooking appliances permitted are limited to ovens, cooktops, ranges, warmers and microwaves.
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SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE
- Domestic cooking hoods installed and constructed in accordance with Section 504.3 of the California Mechanical Code shall be provided over cooktops or ranges.
- A shutoff for the fuel and electrical supply to the cooking equipment shall be provided in a location to which only staff has
access.
A timer shall be provided that automatically deactivates the cooking appliances within a period of not more than 120 minutes.
A portable fire extinguisher shall be provided. Installation shall be in accordance with Section 906 and the extinguisher shall be located within a 30-foot (9144 mm) distance of travel from each domestic cooking appliance. 6. The area containing the domestic cooking appliances shall be separated from all other areas by fire partitions constructed complying with Section 708.
SECTION 423—STORM SHELTERS
423.1 General. This section applies to the design and construction of storm shelters constructed as separate detached buildings or constructed as rooms or spaces within buildings for the purpose of providing protection from tornadoes hurricanes and other severe windstorms during the storm. This section specifies where storm shelters are required and provides requirements for the design and construction of storm shelters. Design of facilities for use as emergency shelters after the storm are outside the scope of ICC 500 and shall comply with Table 1604.5 as a Risk Category IV Structure.
423.2 Construction. Storm shelters shall be constructed in accordance with this code and ICC 500 and shall be designated as hurricane shelters, tornado shelters, or combined hurricane and tornado shelters. Buildings or structures that are also designated as emergency shelters shall also comply with Table 1604.5 as Risk Category IV structures.
Any storm shelter not required by this section shall be permitted to be constructed, provided that such structures meet the requirements of this code and ICC 500.
423.3 Occupancy classification. The occupancy classification for a storm shelter shall be determined in accordance with this section.
423.3.1 Dedicated storm shelters. A facility designed to be occupied solely as a storm shelter shall be classified as Group A-3 for the determination of requirements other than those covered in ICC 500.
CEBC § 303.3 High relevance — show source text
Exceptions:
- Where an addition is being added on an existing Group E site, and where the addition is not of sufficient size to accommodate the required occupant capacity of the storm shelter for all of the buildings on-site, the storm shelter shall at a minimum accommodate the required capacity for the addition.
- Where approved by the code official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
303.3 Occupancy classification. The occupancy classification for storm shelters shall be determined in accordance with Section 423.3 of the California Building Code .
SECTION 304—STRUCTURAL DESIGN LOADS AND EVALUATION AND DESIGN PROCEDURES
[BS] 304.1 Live loads. Where an addition or alteration does not result in increased design live load, existing gravity load-carrying structural elements shall be permitted to be evaluated and designed for live loads approved prior to the addition or alteration. If the approved live load is less than that required by Section 1607 of the California Building Code, the area designated for the nonconforming live load shall be posted with placards of approved design indicating the approved live load. Where the addition or alteration results in increased design live load, the live load required by Section 1607 of the California Building Code shall be used.
[BS] 304.2 Snow loads on adjacent buildings. Where an alteration or addition changes the potential snow drift effects on an adjacent building, the code official is authorized to enforce Section 7.12 of ASCE 7.
[BS] 304.3 Seismic evaluation and design procedures. Where required, seismic evaluation or design shall comply with the procedures and criteria in this section, regardless of which compliance method is used. The scope of the required evaluation or design shall be as indicated in applicable provisions of Chapters 4 through 11 .
[BS] 304.3.1 Full seismic criteria. Where required, seismic evaluation or design shall comply with one of the following methodologies, which shall not be applied in combination with each other:
- Section 1613 of the California Building Code . Where the existing seismic force-resisting system is a type that can be designated as “Ordinary,” values of R, Ω 0 and C d used for analysis in accordance with Chapter 16 of the California Building Code shall be those specified for structural systems classified as “Ordinary” in accordance with Table 12.2-1 of ASCE 7, unless it can be demonstrated that the structural system will provide performance equivalent to that of a “Detailed,” “Intermediate” or “Special” system.
- ASCE 41, using a Tier 3 procedure and both levels of the two-level performance objective in Table 304.3.1 for the applicable risk category.
CEBC § 423.1 High relevance — show source text
- A portable fire extinguisher shall be provided. Installation shall be in accordance with Section 906 and the extinguisher shall be located within a 30-foot (9144 mm) distance of travel from each domestic cooking appliance. 6. The area containing the domestic cooking appliances shall be separated from all other areas by fire partitions constructed complying with Section 708.
SECTION 423—STORM SHELTERS
423.1 General. This section applies to the design and construction of storm shelters constructed as separate detached buildings or constructed as rooms or spaces within buildings for the purpose of providing protection from tornadoes hurricanes and other severe windstorms during the storm. This section specifies where storm shelters are required and provides requirements for the design and construction of storm shelters. Design of facilities for use as emergency shelters after the storm are outside the scope of ICC 500 and shall comply with Table 1604.5 as a Risk Category IV Structure.
423.2 Construction. Storm shelters shall be constructed in accordance with this code and ICC 500 and shall be designated as hurricane shelters, tornado shelters, or combined hurricane and tornado shelters. Buildings or structures that are also designated as emergency shelters shall also comply with Table 1604.5 as Risk Category IV structures.
Any storm shelter not required by this section shall be permitted to be constructed, provided that such structures meet the requirements of this code and ICC 500.
423.3 Occupancy classification. The occupancy classification for a storm shelter shall be determined in accordance with this section.
423.3.1 Dedicated storm shelters. A facility designed to be occupied solely as a storm shelter shall be classified as Group A-3 for the determination of requirements other than those covered in ICC 500.
Exceptions:
The occupancy category for dedicated storm shelters with a design occupant capacity of less than 50 persons as determined in accordance with ICC 500 shall be in accordance with Section 303.
The occupancy category for a dedicated residential storm shelter shall be the Group R occupancy served.
423.3.2 Storm shelters within host buildings. Where designated storm shelters are constructed as a room or space within a host building that will normally be occupied for other purposes, the requirements of this code for the occupancy of the building, or the individual rooms or spaces thereof, shall apply unless otherwise required by ICC 500.
423.4 Critical emergency operations. In areas where the shelter design wind speed for tornados in accordance with Figure 304.2(1) of ICC 500 is 250 mph, 911 call stations, emergency operation centers and fire, rescue, ambulance and police stations shall comply with Table 1604.5 as a Risk Category IV structure and shall be provided with a storm shelter constructed in accordance with ICC 500.
423.4.1 Design occupant capacity. The required design occupant capacity of the storm shelter shall include the critical emergency operations on the site and shall be the total occupant load of offices and the number of beds.
Exceptions:
- Where approved by the building official, the actual number of occupants for whom each occupied space, floor or building is designed, although less than that determined by occupant load calculation, shall be permitted to be used in the determination of the required design occupant capacity for the storm shelter.
- Where a new building is being added on an existing site, and where the new building is not of sufficient size to accommodate the required design occupant capacity of the storm shelter for all of the buildings on the site, the storm shelter shall accommodate not less than the required occupant capacity of the new building.
CEBC § 423.4.2 High relevance — show source text
- Where approved by the building official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
423.4.2 Location. Storm shelters shall be located within the building they serve or shall be located where the distance of travel from not fewer than one exterior door of each building to a door of the shelter serving that building does not exceed 1,000 feet (305 m), unless otherwise approved.
423.5 Group E occupancies. In areas where the shelter design wind speed for tornados is 250 mph in accordance with Figure 304.2(1) of ICC 500, all Group E occupancies with an occupant load of 50 or more shall have a storm shelter constructed in accordance with ICC 500.
Exceptions:
- Group E day care facilities.
- Group E occupancies accessory to places of religious worship.
- Buildings meeting the requirements for shelter design in ICC 500.
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SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE
423.5.1 Design occupant capacity. The required design occupant capacity of the storm shelter shall include all of the buildings on the site and shall be the total occupant load of the classrooms, vocational rooms and offices in the Group E occupancy.
Exceptions:
- Where approved by the building official, the actual number of occupants for whom each occupied space, floor or building is designed, although less than that determined by occupant load calculation, shall be permitted to be used in the determination of the required design occupant capacity for the storm shelter.
- Where a new building is being added on an existing Group E site, and where the new building is not of sufficient size to accommodate the required design occupant capacity of the storm shelter for all of the buildings on the site, the storm shelter shall accommodate not less than the required occupant capacity for the new building.
- Where approved by the building official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
423.5.2 Location. Storm shelters shall be located within the buildings they serve or shall be located where the distance of travel from not fewer than one exterior door of each building to a door of the shelter serving that building does not exceed 1,000 feet (305 m).
SECTION 424—PLAY STRUCTURES
[BF] 424.1 General. Play structures installed inside all occupancies covered by this code that exceed 10 feet (3048 mm) in height or 150 square feet (14 m [2] ) in area shall comply with Sections 424.2 through 424.5.
[BF] 424.2 Materials. Play structures shall be constructed of noncombustible materials or of combustible materials that comply with the following:
- Fire-retardant-treated wood complying with Section 2303.2.
- Light-transmitting plastics complying with Section 2606.
- Foam plastics (including the pipe foam used in soft-contained play equipment structures) having a maximum heat-release rate not greater than 100 kilowatts when tested in accordance with UL 1975 or when tested in accordance with NFPA 289, using the 20 kW ignition source.
CEBC § 5.2 High relevance — show source text
Where a separated portion of a building or structure provides required access to, required egress from or shares life safety systems, designated seismic systems, emergency power systems, or emergency and egress lighting systems with another portion having a higher risk category, or provides required electrical, communications, mechanical, plumbing or conveying support to another portion assigned to Risk Category IV, both portions shall be assigned to the higher risk category. Exception: Where a storm shelter designed and constructed in accordance with ICC 500 is provided in a building, structure or portion thereof normally occupied for other purposes, the risk category for the normal occupancy of the building shall apply unless the storm shelter is a designated emergency shelter in accordance with Table 1604 A .5. 1604 A .5.2 Photovoltaic (PV) panel systems. Photovoltaic (PV) panel systems and elevated PV support structures shall be assigned a risk category as follows:
- Ground-mounted PV panel systems serving only Group R-3 buildings shall be assigned to Risk Category I.
- Ground-mounted PV panel systems other than those described in Items 1 and 5 shall be assigned to Risk Category II.
- Elevated PV support structures other than those described in Items 4, 5 and 6 shall be assigned to Risk Category II.
[DSA-SS] The risk category shall not be less than the risk category that corresponds to the usable space underneath in accordance with the risk category and nature of occupancy descriptions in Table 1604A.5. 4. Rooftop-mounted PV panel systems and elevated PV support structures installed on top of buildings shall be assigned to the same risk category as the risk category of the building on which they are mounted. 5. PV panel systems and elevated PV support structures paired with energy storage systems (ESS) and serving as a dedicated, stand-alone source of backup power for Risk Category IV buildings shall be assigned to Risk Category IV. 6. Elevated PV support structures where the usable space underneath is used for parking of emergency vehicles shall be assigned to Risk Category IV. 1604 A .6 In-situ load tests. The building official is authorized to require an engineering analysis or a load test, or both, of any construction whenever there is reason to question the safety of the construction for the intended occupancy. Engineering analysis and load tests shall be conducted in accordance with Section 1708 A .
1604 A .7 Preconstruction load tests. Materials and methods of construction that are not capable of being designed by approved engineering analysis or that do not comply with the applicable referenced standards, or alternative test procedures in accordance with Section 1707 A, shall be load tested in accordance with Section 1709 A .
1604 A .8 Anchorage. Buildings and other structures, and portions thereof, shall be provided with anchorage in accordance with Sections 1604 A .8.1 through 1604 A .8.3, as applicable. 1604 A .8.1 General. Anchorage of the roof to walls and columns, and of walls and columns to foundations, shall be provided to resist the uplift and sliding forces that result from the application of the prescribed loads. 1604 A .8.2 Structural walls. Walls that provide vertical load-bearing resistance or lateral shear resistance for a portion of the structure shall be anchored to the roof and to all floors and members that provide lateral support for the wall or that are supported by the wall.
CEBC § 423.5.2 High relevance — show source text
- Where a new building is being added on an existing Group E site, and where the new building is not of sufficient size to accommodate the required design occupant capacity of the storm shelter for all of the buildings on the site, the storm shelter shall accommodate not less than the required occupant capacity for the new building.
- Where approved by the building official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
423.5.2 Location. Storm shelters shall be located within the buildings they serve or shall be located where the distance of travel from not fewer than one exterior door of each building to a door of the shelter serving that building does not exceed 1,000 feet (305 m).
SECTION 424—PLAY STRUCTURES
[BF] 424.1 General. Play structures installed inside all occupancies covered by this code that exceed 10 feet (3048 mm) in height or 150 square feet (14 m [2] ) in area shall comply with Sections 424.2 through 424.5.
[BF] 424.2 Materials. Play structures shall be constructed of noncombustible materials or of combustible materials that comply with the following:
Fire-retardant-treated wood complying with Section 2303.2.
Light-transmitting plastics complying with Section 2606.
Foam plastics (including the pipe foam used in soft-contained play equipment structures) having a maximum heat-release rate not greater than 100 kilowatts when tested in accordance with UL 1975 or when tested in accordance with NFPA 289, using the 20 kW ignition source.
Aluminum composite material (ACM) meeting the requirements of Class A interior finish in accordance with Chapter 8 when tested as an assembly in the maximum thickness intended for use.
Textiles and films complying with the fire propagation performance criteria contained in Test Method 1 or Test Method 2, as appropriate, of NFPA 701.
Plastic materials used to construct rigid components of soft-contained play equipment structures (such as tubes, windows, panels, junction boxes, pipes, slides and decks) exhibiting a peak rate of heat release not exceeding 400 kW/ m [2] when tested in accordance with ASTM E1354 at an incident heat flux of 50 kW/m [2] in the horizontal orientation at a thickness of 6 mm.
Ball pool balls, used in soft-contained play equipment structures, having a maximum heat-release rate not greater than 100 kilowatts when tested in accordance with UL 1975 or when tested in accordance with NFPA 289, using the 20 kW ignition source. The minimum specimen test size shall be 36 inches by 36 inches (914 mm by 914 mm) by an average of 21 inches (533 mm) deep, and the balls shall be held in a box constructed of galvanized steel poultry netting wire mesh.
Foam plastics shall be covered by a fabric, coating or film meeting the fire propagation performance criteria contained in Test Method 1 or Test Method 2, as appropriate, of NFPA 701.
The floor covering placed under the play structure shall exhibit a Class I interior floor finish classification, as described in Section 804, when tested in accordance with ASTM E648 or NFPA 253.
CEBC § 1.10.1 High relevance — show source text
CHAPTER TOPICS Col2 CHAPTER SUBJECTS 1, 2 Administrative Requirements and Definitions 3 Provisions for all Compliance Methods 4 Repairs 5 Prescriptive Compliance Method for Existing Buildings 6–11 Work Area Compliance Method for Existing Buildings 13 Performance Compliance Method for Existing Buildings 14 Relocated Buildings 15 Construction Safeguards 16 Referenced Standards Appendix A Guidelines for Seismic Retrofit of Existing Buildings Appendix B Supplementary Accessibility Requirements for Existing Buildings Appendix C Guidelines for Wind Retrofit of Existing Buildings Appendix D Board of Appeals Appendix E Temporary Emergency Uses Resource A Guidelines on Fire Ratings of Archaic Materials and Assemblies CALIFORNIA BUILDING CODE CORRELATED TOPICS
The CEBC requirements for construction safeguards are directly correlated to the requirements of the CBC. The following table shows chapters of the CBC that are correlated with the CEBC:
CEBC/CBC CORRELATED TOPICS Col2 Col3 CEBC CHAPTER/SECTION CBC CHAPTER/SECTION SUBJECT Chapter 15 Chapter 33 Construction safeguards Chapter 1 Scope and Administration.
Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.
Chapter 2 Definitions.
Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.
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Chapter 3 Provisions for All Compliance Methods.
Chapter 3 guides the use of the three compliance methods of the CEBC and provides requirements that apply globally. The globally applicable requirement include general requirements related to buildings materials and other applicable codes, storm shelters, structural loads, in-situ load tests, accessibility, smoke alarms, carbon monoxide detection and exterior wall coverings.
Chapter 3A Provisions for All Compliance Methods.
Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 4 Repairs.
Chapter 4, a chapter independent of the three compliance methods, governs the repair of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.
Chapter 4A Repairs.
Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of State- wide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
CEBC § 1.10.1 High relevance — show source text
xii 2025 CALIFORNIA EXISTING BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
Chapter 3 Provisions for All Compliance Methods.
Chapter 3 guides the use of the three compliance methods of the CEBC and provides requirements that apply globally. The globally applicable requirement include general requirements related to buildings materials and other applicable codes, storm shelters, structural loads, in-situ load tests, accessibility, smoke alarms, carbon monoxide detection and exterior wall coverings.
Chapter 3A Provisions for All Compliance Methods.
Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 4 Repairs.
Chapter 4, a chapter independent of the three compliance methods, governs the repair of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.
Chapter 4A Repairs.
Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of State- wide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 5 Prescriptive Compliance Method.
Chapter 5 provides one of the three main options of compliance available in the CEBC for buildings and structures undergoing alteration, addition or change of occupancy. The base requirements are more administrative in nature. The structural triggers for upgrades are consistent with the Work Area Method.
Chapter 5A Prescriptive Compliance Method.
Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 6 Classification of Work.
Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.
Chapter 7 Alterations—Level 1.
Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.
Chapter 8 Alterations—Level 2.
A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.
Chapter 9 Alterations—Level 3.
CEBC § 1.1.2 High relevance — show source text
1.1.2 Purpose. The purpose of this code is to establish the minimum requirements to safeguard the public health, safety and general welfare through structural strength, means of egress facilities, stability, access to persons with disabilities, sanitation, adequate lighting and ventilation and energy conservation; safety to life and property from fire and other hazards attributed to the built environment; and to provide safety to firefighters and emergency responders during emergency operations.
1.1.3 Scope. The provisions of this code shall apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures throughout the State of California. [HCD 1 & 2] The provisions of this code shall apply to repair, alteration, change of occupancy, addition to and relocation of every existing building or structure or any appurtenances connected or attached to such buildings or structures throughout the State of California.
1.1.3.1 Nonstate-regulated buildings, structures and applications. Except as modified by local ordinance pursuant to Section 1.1.8, the following standards in the California Code of Regulations, Title 24, Parts 2, 2.5, 3, 4, 5, 6, 7, 9, 10 and 11 shall apply to all occupancies and applications not regulated by a state agency.
1.1.3.2 State-regulated buildings, structures and applications. The model code, state amendments to the model code and/or state amendments where there are no relevant model code provisions shall apply to the following buildings, structures and applications regulated by state agencies as specified in Sections 1.2 through 1.14, except where modified by local ordinance pursuant to Section 1.1.8. When adopted by a state agency, the provisions of this code shall be enforced by the appropriate enforcing agency, but only to the extent of authority granted to such agency by the state legislature.
Note: See “How to Distinguish Between Model Code Language and California Amendments” in the front of the code. 1. State-owned buildings, including buildings constructed by the Trustees of the California State University, and to the extent permitted by California laws, buildings designed and constructed by the Regents of the University of California, and regulated by the Building Standards Commission. See Section 1.2 for additional scope provisions. 2. Section 1.3 is reserved for the Board of State Community Corrections. 3. Section 1.4 is reserved for the Department of Consumer Affairs. 4. Section 1.5 is reserved for the California Energy Commission. 5. Section 1.6 is reserved for the Department of Food and Agriculture. 6. Section 1.7 is reserved for the Department of Public Health. 7. Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping _accommodations with or without common toilets or cooking facilities.
Frequently asked questions
Do the CEBC storm-shelter rules apply to small residential projects?
No. The CEBC trigger in § 303 is focused on additions to Group E and critical facilities; residential storm shelters are governed by the CBC/IRC provisions and ICC 500 standards referenced there. CEBC § 303.1 governs shelters broadly but the specific CEBC mandatory trigger is in § 303.2 for Group E additions.
If I build a new detached storm shelter on site, do I still need to follow CEBC?
Yes — any storm shelter constructed for protection during severe windstorms must meet ICC 500 and CBC Section 423 as required by § 303.1.1, and CEBC requirements for additions and site occupant-capacity calculations still apply where they are triggered.
Can the required shelter capacity be reduced?
Possibly. § 303.2.1 permits two reductions: (1) when an addition cannot physically accommodate the full site requirement, the shelter must at least serve the addition; and (2) with building-official approval, required capacity may be reduced by the capacity of existing approved shelters on the site.
Where do I find the wind-speed map used to determine the 250 mph threshold?
CEBC refers you to ICC 500 Figure 304.2(1) for the shelter-design wind speed map; the CEBC trigger in § 303.2 uses that map to establish whether the site falls into the 250 mph zone.
Are travel-distance limits always waived for Group E additions?
No. CEBC § 303.1.1 creates a specific exception to the CBC travel-distance provisions for storm shelters added to critical emergency operations facilities or Group E occupancies, but this is a limited exception; other ICC 500 and CBC requirements remain applicable. Confirm with the building official.
More in California Existing Building Code
- Administration and Definitions (Scope, enforcement, code official duties, definitions)
- Provisions for All Compliance Methods (general requirements that apply to all compliance options; Chapter 3 / 3A)
- Seismic retrofit and evaluation (Appendix A and seismic provisions/sections for evaluation and retrofit)
- Referenced Standards and Appendices (Chapter 16 and Appendices A–E, Resource A)
- Repairs (Chapter 4 — repair-specific rules for materials, means of egress, structural, MEP, etc.)
- Alterations — Level 1, Level 2, Level 3 (technical requirements for each alteration level; Chapters 7–9)
- Change of Occupancy and Additions (requirements for occupancy changes and additions; Chapters 10–11)
- Compliance Methods — Prescriptive, Work Area, Performance (Chapters 5, 6–11, 13)
- Relocated Buildings (requirements for buildings moved or relocated; Chapter 14)
- Construction Safeguards (site safety, means of egress and life-safety during construction; Chapter 15)
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