CEBC · California Existing Building Code

When must relocated buildings be upgraded for snow loads?

If you move a building to a place with higher snow loads, CEBC **§ 1402.5** requires the building to be upgraded to meet the CBC/CRC snow-load requirements for the new site — but individual structural elements whose stress increases by **5% or less** may remain unchanged; have a licensed engineer run the numbers and document any required strengthening.

Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

Relocated buildings must meet the California Building Code or California Residential Code snow load requirements at the new site when the snow loads at the new location are higher than those at the previous location. This rule is stated in § 1402.5 of the California Existing Building Code (CEBC). The CEBC provides a single numerical exception: existing structural elements that would experience a stress increase of no more than 5 percent may remain unchanged. § 1402.5 — CEBC.

If a building is moved to a place with greater snow loads, it must be brought up to the snow-load requirements for that new location — except for elements whose stress goes up by 5% or less.


Requirements in detail

Short plain-English restatement (controlling text)

  • The CEBC says: If snow loads at the new location are higher than at the previous location, the structure must comply with the CBC/CRC snow provisions. The controlling text is § 1402.5.

What "comply" means here

  • “Comply” means design and verify structural members, connections and roof systems for the applicable design snow loads using the same snow-load provisions required for new construction in the California Building Code or California Residential Code (as applicable). See § 1402.5.
  • Use the CBC/CRC procedures to determine the applicable ground and roof snow loads at the new site (for example, see CBC guidance on snow loads, including the snow-load section used for new-design values).

Exception

  • Individual structural elements whose computed stress is increased by 5 percent or less as a result of the move are not required to be upgraded. This numeric threshold is part of § 1402.5.

Decision table — when to upgrade (quick reference)

Decision factor Threshold / value Required action Code reference
Trigger condition New-location snow load > previous-location snow load Upgrade to comply with CBC/CRC snow provisions for the new location § 1402.5 — CEBC.
Exception (element-level) Stress increase ≤ 5% No upgrade required for that element § 1402.5 — CEBC.
How to get design snow loads Use CBC/CRC snow-load provisions (determine ground/roof snow loads per code) Apply CBC/CRC required design values and combinations See CBC snow provisions (e.g., Section on snow loads) and CEBC reference to CBC/CRC.
Related structural threshold for other loads Wind/seismic exceptions use different % thresholds (see wind/seismic sections) Compare to wind/seismic rules when relocating § 1402.3 and § 1402.4 — CEBC.

Exceptions & special cases

  • Element-level relief: Any individual structural element whose computed stress increase is no more than 5% may remain unaltered — § 1402.5. This is an element-level, not whole-building, exception.
  • Compare with other relocated-load rules: For wind the CEBC provides exceptions (e.g., 10% stress increase) and for seismic there are different limits and SD category conditions; those are in § 1402.3 and § 1402.4 respectively — don’t conflate the numeric thresholds.
  • If relocation places the building in other hazard areas (floods, etc.), other Chapter 14 provisions apply (for example § 1402.6 for flood hazard areas).
  • The CEBC requires the code official to inspect relocated buildings and to require repairs if damage is found; such inspections may drive upgrades beyond snow-load compliance (see § 1402.7).

Common mistakes

  • Assuming any increase in required snow load is automatically exempt because only small changes are occurring — the CEBC allows exemption only where the stress increase is ≤ 5% for an element. Check the actual computed stress increase; don’t guess. § 1402.5.
  • Comparing informal local observations of “more snow” instead of using the formal CBC/CRC design snow loads for the two sites. The CEBC ties compliance to the code-required design snow loads used for new construction.
  • Forgetting roof-drifts and load combinations. When you design for the new snow load, include drift and accumulation effects as the CBC/CRC require (i.e., apply the same load provisions used for new buildings).
  • Treating the 5% rule as a whole-building tolerance — the exception is written for structural elements; many components may still need upgrading even when a few elements qualify for the exception. § 1402.5.

Worked example — concrete scenario

Scenario: A single-story roofed structure (original site) was designed for a flat-roof snow load of 10 psf. The building is relocated to a mountain neighborhood where the CBC/CRC design flat-roof snow load is 30 psf.

  1. Trigger check: new location snow load (30 psf) > old location snow load (10 psf) → upgrade required per § 1402.5.
  2. Determine member demand change (illustrative):
    • Suppose a roof rafter had a demand (bending stress) proportional to the roof uniform load. Rough proportionality: demand scales with load magnitude.
    • New demand ≈ (30 psf / 10 psf) = 3.0 × old demand → 200% increase in demand (i.e., +200%).
  3. Compare to exception:
    • The demand increase (200%) >> 5% exception threshold → the rafter must be upgraded or replaced to meet CBC/CRC snow-load requirements at the new site (per § 1402.5).
  4. Practical next steps:
    • Engineer evaluates each gravity-load element for the new snow loads and specifies strengthening or replacement where stress increases exceed 5%. The design values and combinations must follow the CBC/CRC rules for snow loads.

Note: The simple proportional calculation above is illustrative. A licensed design professional must perform the actual structural analysis, including load combinations, drift effects, tributary areas and connection capacities, per CBC/CRC procedures. The CEBC requires compliance with those CBC/CRC provisions when the triggering condition in § 1402.5 is met.


Related provisions

  • § 1402.2 — Foundation requirements for relocated buildings (CEBC). Relocated buildings must meet CBC/CRC foundation provisions as applicable.
  • § 1402.3 — Wind loads for relocated buildings (CEBC); includes exceptions and different numeric thresholds.
  • § 1402.4 — Seismic loads for relocated buildings (CEBC); contains separate exception language and SD-category conditions.
  • § 1402.6 — Flood hazard areas (CEBC) — special rule when moving into flood zones.
  • § 1402.7 — Required inspection and repairs after relocation (CEBC) — code official authority to inspect and require repairs.
  • CBC snow provisions (design snow-load rules used for new construction) — see the California Building Code snow-load sections referenced by the CEBC; for example, CBC references to snow-load procedures appear in the CBC structural chapters.

Code references

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

  • CEBC § 1401.1.1 High relevance — show source text

    and the California Code of Regulations, Title 25, Division 1, Chapter 2._ Manufactured homes must meet unit identification (data plate) and certification label requirements as specified in the Code of Federal Regulations, Title 24, Subtitle B, Chapter XX, Part 3280 and Health and Safety Code Section 18032. Commercial modulars and special purpose commercial modulars must meet identification requirements in the California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 2.

    1401.1.1 Bleachers, folding and telescopic seating and grandstands. Relocated or moved bleachers, folding and telescopic seating and grandstands shall comply with ICC 300.

    1401.2 Conformance. The building shall be safe for human occupancy as determined by the California Fire Code and the Interna- tional Property Maintenance Code . Any repair, alteration or change of occupancy undertaken within the moved structure shall comply with the requirements of this code applicable to the work being performed. Any field-fabricated elements shall comply with the requirements of the California Building Code or the California Residential Code, as applicable. [HCD 1 & HCD 2] After July 1, 1978, local ordinances or regulations for relocated or moved apartment houses and dwellings shall permit the retention of existing materials and methods of construction, provided the apartment house or dwelling complies with the building standards for foundations applica- ble to new construction and does not become or continue to be a substandard building. For additional information, see Health and Safety Code Section 17958.9.

    SECTION 1402—REQUIREMENTS

    1402.1 Location on the lot. The building shall be located on the lot in accordance with the requirements of the California Building Code or the California Residential Code, as applicable.

    [BS] 1402.2 Foundation. The foundation system of relocated buildings shall comply with the California Building Code or the Califor- nia Residential Code, as applicable.

    [BS] 1402.2.1 Connection to the foundation. The connection of the relocated building to the foundation shall comply with the California Building Code or the California Residential Code, as applicable.

    [BS] 1402.3 Wind loads. Buildings shall comply with California Building Code or California Residential Code wind provisions, as applicable.

    Exceptions:

    1. Detached one- and two-family dwellings and Group U occupancies where wind loads at the new location are not higher than those at the previous location.
    2. Structural elements whose stress is not increased by more than 10 percent.

    [BS] 1402.4 Seismic loads. Buildings shall comply with California Building Code or California Residential Code seismic provisions at the new location, as applicable.

    Exceptions:

    1. Structures in Seismic Design Categories A and B and detached one- and two-family dwellings in Seismic Design Categories A, B and C where the seismic loads at the new location are not higher than those at the previous location.
    2. Structural elements whose stress is not increased by more than 10 percent.

    [BS] 1402.5 Snow loads. Structures shall comply with California Building Code or California Residential Code snow loads, as applicable, where snow loads at the new location are higher than those at the previous location.

    Exception: Structural elements whose stress is not increased by more than 5 percent.

  • CEBC § 1402.2 High relevance — show source text

    [BS] 1402.2 Foundation. The foundation system of relocated buildings shall comply with the California Building Code or the Califor- nia Residential Code, as applicable.

    [BS] 1402.2.1 Connection to the foundation. The connection of the relocated building to the foundation shall comply with the California Building Code or the California Residential Code, as applicable.

    [BS] 1402.3 Wind loads. Buildings shall comply with California Building Code or California Residential Code wind provisions, as applicable.

    Exceptions:

    1. Detached one- and two-family dwellings and Group U occupancies where wind loads at the new location are not higher than those at the previous location.
    2. Structural elements whose stress is not increased by more than 10 percent.

    [BS] 1402.4 Seismic loads. Buildings shall comply with California Building Code or California Residential Code seismic provisions at the new location, as applicable.

    Exceptions:

    1. Structures in Seismic Design Categories A and B and detached one- and two-family dwellings in Seismic Design Categories A, B and C where the seismic loads at the new location are not higher than those at the previous location.
    2. Structural elements whose stress is not increased by more than 10 percent.

    [BS] 1402.5 Snow loads. Structures shall comply with California Building Code or California Residential Code snow loads, as applicable, where snow loads at the new location are higher than those at the previous location.

    Exception: Structural elements whose stress is not increased by more than 5 percent.

    [BS] 1402.6 Flood hazard areas. If relocated or moved into a flood hazard area, structures shall comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.

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    RELOCATED OR MOVED BUILDINGS

    [BS] 1402.7 Required inspection and repairs. The code official shall be authorized to inspect, or to require approved professionals to inspect at the expense of the owner, the various structural parts of a relocated building to verify that structural components and connections have not sustained structural damage. Any repairs required by the code official as a result of such inspection shall be made prior to the final approval.

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    CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 15 – CONSTRUCTION SAFEGUARDS

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

    Adopting Agency BSC BSC-
    CG
    SFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting
  • CEBC § 5A-5 High relevance — show source text

    503 A .3 Existing structural elements carrying gravity load. Any existing gravity load-carrying structural element for which an alteration causes an increase in design dead, live or snow load, including snow drift effects, of more than 5 percent shall be replaced or altered as needed to carry the gravity loads required by the California Building Code for new structures. Any existing gravity loadcarrying structural element whose gravity load-carrying capacity is decreased as part of the alteration shall be shown to have the capacity to resist the applicable design dead, live and snow loads including snow drift effects required by the California Building Code for new structures.

    503 A .4 Existing structural elements carrying lateral load. Except as permitted by Section 503 A .13, where the alteration increases design lateral loads, results in a prohibited structural irregularity as defined in the California Building Code, ASCE 7, or decreases the

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    PRESCRIPTIVE COMPLIANCE METHOD

    capacity of any existing lateral load-carrying structural element, the lateral force-resisting system of the altered building or structure shall meet the requirements of Section s 1609 A and 1613A of the California Building Code .

    Exceptions: For incidental and minor alterations:

    1. Any existing lateral load-carrying structural element whose demand-capacity ratio with the alteration considered is not more than 10 percent greater than its demand-capacity ratio with the alteration ignored shall be permitted to remain unaltered. For purposes of calculating demand-capacity ratios, the demand shall consider applicable load combinations with design lateral loads or forces in accordance with Section s 1609 A and 1613A of the California Building Code . Reduced seismic forces, to 75 percent of those in Section 1613A, shall be permitted. The same methodology shall be used for the altered and unaltered structures. For purposes of this exception, comparisons of demand-capacity ratios and calculation of design lateral loads, forces and capacities shall account for the cumulative effects of additions and alterations since original construction. When calculating demand-capacity ratios for wind, the date of original construction shall be permitted to be taken as the date of completion of a prior addition, alteration or repair in compliance with Section 1609 A of the California Building Code or the code wind forces in effect at the time. When calculating demand-capacity ratios for earthquake, the date of original construction shall be permitted to be taken as the date of completion of a prior addition, alteration or repair in compliance with Section 304A.3.4 of this code, or the full or reduced seismic forces in effect at the time.

    2. Buildings in which the increase in the demand-capacity ratio is due entirely to the addition of rooftop-supported mechanical equipment individually having an operating weight less than 400 pounds (181.4 kg) and where the total additional weight of all rooftop equipment placed after initial construction of the building is less than 10 percent of the roof dead load. For purposes of this exception, “roof” shall mean the roof level above a particular story.

  • CEBC § 5.4.3 High relevance — show source text
    1. If the new panel is able to accommodate it, the existing service conductor may be reused provided it meets the load, voltage drop, and flicker requirements of the new load. If the service conductor size must be upgraded, the existing conduit must be proofed with a mandrel.

    2. For existing panels that are less than 36” horizontally away from the gas service riser; it is allowed to use the existing service conduit and extend new conduit of the same size and material to a new panel location that is 36” or more away from the gas riser as long as all the parameters listed in Notes 21, 22 and 23 are met. This note only applies to panels that requires a total number of two service conduits.

    A. For service runs that approach the front of the existing panel, directly or at an angle, the new conduit will need to start back along the existing conduit and far enough away from the new panel location to minimize additional bends in the conduit system.

    B. The new total number of bends must be within the maximum 315 ° allowed for service conduit run. For further information, refer to Document 038193.

    C. The new panel must be relocated no more than 20’ away from the existing panel.

    1. Notes 21, 22 and 23 above do not apply to the following conditions .

    A. Direct buried or Cable-In-Conduit (CIC) service cables. Direct buried and CIC service cables must be replaced with approved service cable and installed in approved service conduit.

    (1) Splice boxes between the customer panel,with existing DB or CIC cable, and PG&E secondary distribution system are not allowed. Service cable needs to be brought up to our current standard conduit service system from the customer meter to PG&E point of secondary distribution.

    B. Upgraded electric meter panels that are within 36 inches of the gas service riser. The clearance requirements in Electric and Gas Service Requirements (Greenbook)Section 5.4.3 ., “Meter Set Clearance Requirements,” must be met for upgraded and relocated meter panels.

    C. New upgraded panels with a Service Equipment Rating (amps) that is more than one upgraded size than the existing panel, as specified in Table 4 on Page 6 and Table 5 on Page 7. For example, if an existing panel less than or equal to 100 amps is upgraded to a 400 amp panel instead of a 200 amp panel.

    D. If the existing cable size is more than one size smaller than the cable required to serve maximum load for the new panel, as specified in Table 4 on Page 6 and Table 5 on Page 7. For example, if the existing cable is #2 AWG aluminum and new upgraded panel requires 4/0 aluminum.

    Rev. #26: 03−25−22 063928 Page 5 of 9

    UG-1: Services Greenbook EDM

    Methods and Requirements for Installing Non-Residential Underground Electric Services 0 − 600 Volts to Customer-Owned Facilities

    Temporary Service

  • CEBC § 0.35 Medium relevance — show source text

    Required diaphragm lengths are to be provided at each end of the structure.
    e. Multiplying required diaphragm lengths by 0.35 is permitted if all panel edges are blocked.
    f. Multiplying required diaphragm lengths by 0.9 is permitted if all panel edges are secured with screws spaced at 4 inches o.c.
    g. To determine the minimum diaphragm length for buildings with ceiling heights of 9 feet or 10 feet values in this table shall be multiplied by 1.15.|For SI: 1 inch = 25.4 mm, 1 mile per hour = 0.447 m/s, 1 foot = 304.8 mm, 1 mil = 0.0254 mm.
    a. Ceiling diaphragm is composed of1/2-inch gypsum board (min. thickness) secured with screws spaced at 6 inches o.c. at panel edges and 12 inches o.c. infield. Use No. 8
    screws (min.) where framing members have a designation thickness of 54 mils or less and No. 10 screws (min.) where framing members have a designation thickness greater
    than 54 mils.
    b. Maximum aspect ratio (length/width) of diaphragms is 2:1.
    c. Building width is in the direction of horizontal framing members supported by the wall studs.
    d. Required diaphragm lengths are to be provided at each end of the structure.
    e. Multiplying required diaphragm lengths by 0.35 is permitted if all panel edges are blocked.
    f. Multiplying required diaphragm lengths by 0.9 is permitted if all panel edges are secured with screws spaced at 4 inches o.c.
    g. To determine the minimum diaphragm length for buildings with ceiling heights of 9 feet or 10 feet values in this table shall be multiplied by 1.15.|For SI: 1 inch = 25.4 mm, 1 mile per hour = 0.447 m/s, 1 foot = 304.8 mm, 1 mil = 0.0254 mm.
    a. Ceiling diaphragm is composed of1/2-inch gypsum board (min. thickness) secured with screws spaced at 6 inches o.c. at panel edges and 12 inches o.c. infield. Use No. 8
    screws (min.) where framing members have a designation thickness of 54 mils or less and No. 10 screws (min.) where framing members have a designation thickness greater
    than 54 mils.
    b. Maximum aspect ratio (length/width) of diaphragms is 2:1.
    c. Building width is in the direction of horizontal framing members supported by the wall studs.
    d. Required diaphragm lengths are to be provided at each end of the structure.
    e. Multiplying required diaphragm lengths by 0.35 is permitted if all panel edges are blocked.
    f. Multiplying required diaphragm lengths by 0.9 is permitted if all panel edges are secured with screws spaced at 4 inches o.c.
    g. To determine the minimum diaphragm length for buildings with ceiling heights of 9 feet or 10 feet values in this table shall be multiplied by 1.15.|

    FIGURE R804.3.7.1(1)—CEILING DIAPHRAGM TO GABLE ENDWALL DETAIL

    CEILING JOISTS

    FLAT STUD OR TRACK BLOCKING AT 48 IN. O.C. AT FIRST TWO JOIST SPACES

  • CEBC § 2-6 Medium relevance — show source text

    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.
    3. The capacity of any structural component carrying snow load, or any group of such components, that supports more than 30 percent of the roof area of similar construction has been reduced more than 20 percent from its predamage condition, and the remaining capacity with respect to dead, live and snow loads is less than 75 percent of that required by the Califor- nia Building Code for new buildings of similar structure, purpose and location.

    For purposes of this definition, work done to implement repairs shall not be considered damage that reduces structural capacity.

    SUBSTANTIAL STRUCTURAL DAMAGE. [OSHPD 1 & 1R] 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 10 percent from its predamage condition. 2. The capacity of any vertical component carrying gravity load, or any group of such components, has a tributary area more than 15 percent of the total area of the structure’s floor(s) and roof(s), has been reduced more than 10 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. 3. The capacity of any structural component carrying snow load, or any group of such components, that supports more than 15 percent of the roof area of similar construction, has been reduced more than 10 percent from its predamage condition, and the

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    DEFINITIONS

  • CEBC § 2.3.2 Medium relevance — show source text

    405 A .2.3.2 Extent of repair for compliant buildings. If the evaluation establishes that the building in its predamage condition complies with the provisions of Section 405.2.3.1, then the damaged elements shall be permitted to be restored to their predamage condition.

    405 A .2.3.3 Extent of repair for noncompliant buildings. If the evaluation does not establish that the lateral force-resisting system of the building in its predamage condition complies with the provisions of Section 405.2.3.1, then the lateral forceresisting system, and its foundation, shall be retrofitted to comply with the provisions of this section. The wind loads for the repair and retrofit shall be those required by the building code in effect at the time of original construction, unless the damage was caused by wind, in which case the wind loads shall be in accordance with the California Building Code . The earthquake loads shall not be less than those required by the building code in effect at the time of original construction but not less than 75 percent of those prescribed in California Building Code Section 1613A. Alternatively, where the earthquake damage has not resulted in disproportionate earthquake damage or did not result in collapse, the retrofit shall be permitted to be performed in accordance with Section 304A.3.4.4 for SPC-2 buildings, Section 304A.3.4.5 for SPC-3, SPC-4D and SPC-4 buildings and Section 304A.3.4.6 for SPC-5 buildings. For SPC-5 buildings, the seismic hazard shall be permitted to be reduced to BSE-1E and BSE-2E. Use of Section 304A.3.4.5 to rehabilitate SPC-3, SPC-4D and SPC-4 buildings will result in re-classification of the building to SPC-4D. Noncompliant SPC-4 buildings may be rehabilitated to SPC-5 in accordance with Section 304A.3.4.6 using the reduced seismic hazard. New structural members and connections required by this rehabilitation design shall comply with the detailing provisions of this code for new buildings of similar structure, purpose and location.

    405 A .2.4 Substantial structural damage to gravity load-carrying components. Gravity load-carrying components that have sustained substantial structural damage shall be retrofitted to comply with the applicable provisions for dead, live and snow loads in the California Building Code . Undamaged gravity load-carrying components, including undamaged foundation components, that receive dead, live or snow loads from retrofitted components shall also be retrofitted if required to comply with these design loads. New structural members and connections required by this rehabilitation design shall comply with the detailing provi- sions of this code for new buildings of similar structure, purpose and location.

    405 A .2.4.1 Lateral force-resisting elements. Regardless of the level of damage to vertical elements of the lateral force-resisting system, if substantial structural damage to gravity load-carrying components was caused primarily by wind or seismic effects, then the building shall be evaluated in accordance with Section 405 A .2.3.1 and, if noncompliant, retrofitted in accordance with Section 405 A .2.3.3.

    Exceptions:

  • CBC § 301 Medium relevance — show source text

    The IEBC is a model code in the International Code family of codes intended to provide requirements for repair and alternative approaches for alterations, changes of occupancy and additions to existing buildings. A large number of existing buildings and structures do not comply with the current building code requirements for new construction. Although many of these buildings are potentially salvageable, rehabilitation is often cost-prohibitive because compliance with all the requirements for new construction could require extensive changes that go well beyond the value of the building or the original scope of the alteration. At the same time, it is necessary to regulate construction in existing buildings that undergo additions, alterations, extensive repairs or change of occupancy. Such activity represents an opportunity to ensure that new construction complies with the current building codes and that existing conditions are maintained, at a minimum, to their current level of compliance or are improved as required to meet basic safety levels. To accomplish this objective, and to make the alteration process easier, this code allows for options for controlled departure from full compliance with the International Codes dealing with new construction, while maintaining basic levels for fire safety, structural and life safety features of the rehabilitated building.

    This code provides three main options for a designer in dealing with alterations of existing buildings. These are laid out in Section 301 of this code:

    Option 1: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Prescriptive Compliance Method given in Chapter 5. It should be noted that this method originates from the former Chapter 34 of the IBC (2012 and earlier editions).

    Option 2: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Work Area Compliance Method given in Chapters 6 through 12.

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    Option 3: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Performance Compliance Method given in Chapter 13. It should be noted that this option was also provided in the former Chapter 34 of the IBC (2012 and earlier editions).

    Under limited circumstances, a building alteration can be made to comply with the laws under which the building was originally built, as long as the accessibility requirements are met, there has been no substantial structural damage and there will be limited structural alteration. Flood hazard provisions also must still be addressed where there is a substantial improvement.

    Note that all repairs must comply with Chapter 4 and all relocated buildings are addressed by Chapter 14.

    ARRANGEMENT AND FORMAT OF THE 2025 CEBC

    The format of the CEBC allows each chapter to be devoted to a particular subject. The following table shows how the CEBC is divided. The subsequent table shows CEBC requirements that are correlated with other California Codes. The chapter synopses detail the scope and intent of the provisions of the CEBC.

  • CEBC § 1.10.1 Medium 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).

  • CBC § 301 Medium relevance — show source text

    This code provides three main options for a designer in dealing with alterations of existing buildings. These are laid out in Section 301 of this code:

    Option 1: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Prescriptive Compliance Method given in Chapter 5. It should be noted that this method originates from the former Chapter 34 of the IBC (2012 and earlier editions).

    Option 2: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Work Area Compliance Method given in Chapters 6 through 12.

    2025 CALIFORNIA EXISTING BUILDING CODE xi

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

    Option 3: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Performance Compliance Method given in Chapter 13. It should be noted that this option was also provided in the former Chapter 34 of the IBC (2012 and earlier editions).

    Under limited circumstances, a building alteration can be made to comply with the laws under which the building was originally built, as long as the accessibility requirements are met, there has been no substantial structural damage and there will be limited structural alteration. Flood hazard provisions also must still be addressed where there is a substantial improvement.

    Note that all repairs must comply with Chapter 4 and all relocated buildings are addressed by Chapter 14.

    ARRANGEMENT AND FORMAT OF THE 2025 CEBC

    The format of the CEBC allows each chapter to be devoted to a particular subject. The following table shows how the CEBC is divided. The subsequent table shows CEBC requirements that are correlated with other California Codes. The chapter synopses detail the scope and intent of the provisions of the CEBC.

    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.

  • CEBC § 501A.3.2 Medium relevance — show source text

    501A.3.2 or_ 304A.3.4.5, but not a combination thereof, shall be considered to satisfy the requirements of SPC-4D. 1. Approval of construction documents based on building characterization in accordance with the California Administrative Code (CAC) Chapter 6 Section 2.1.2.1, material properties in accordance with the CAC Chapter 6 Section 2.1.2.2 and Section 304A.5.3 of this code, and a complete rational structural analysis shall be required. 2. Where the SPC-4D upgrade involves construction, a building permit prior to construction shall be required. 3. Where multiple building permits are used to upgrade a building to SPC-4D, a complete rational structural analysis to justify compliance with SPC-4D, for the building in its final configuration, shall be submitted as part of the construction documents submittal to the Office for the last project. 4. Where the SPC-4D upgrade involves construction, buildings shall be assigned to SPC-4D after all projects required for SPC- 4D are closed in compliance.

    304A.3.4 Performance objectives of performance-based methods. Except for the modifications as set forth in Sections 304A.3.4, 304A.3.5 (for ASCE 41-13), and 304A.3.6 (for ASCE 41-23) of this code, all additions, alterations, repairs and seismic retrofit to existing structures or portions thereof shall be permitted to be designed in accordance with the provisions of ASCE 41-23.

    Use of ASCE 41-13 shall be limited to SPC-2 and SPC-4D buildings only.

    When load combinations which do not include seismic forces are required, the new building code provisions of the California Building Code shall be applicable. Required building performance objectives under ASCE 41-23 shall be as follows:

    304A.3.4.1 For general acute care hospital buildings along with all structures required for their continuous operation or access/egress: 1. Immediate Occupancy (IO) Structural Performance Level (S-1) in accordance with ASCE 41-23 Table 2-1 at Basic Safety Earthquake 1N (BSE-1N) Seismic Hazard Level; and 2. Life Safety (LS) Structural Performance Level (S-3) in accordance with ASCE 41-23 Table 2-1 at Basic Safety Earthquake 2N (BSE-2N) Seismic Hazard Level; and

    3. The nonstructural components shall satisfy the requirements of this code for new construction.

    Exception: Performance objectives for upgrading nonconforming hospital buildings to SPC-4D and for incidental or minor alter- ations or repairs of SPC-4D buildings shall be in accordance with Section 304A.3.4.5 of this code.

  • CEBC § 1009.1 Medium relevance — show source text

    1009.1 Moving walk 1003.7 Number 1001.2, 1006 Occupant load 1004 Parking 406.5.7 Protruding objects 1003.3, 1005.7 Ramps 1012, 1019, 1027 Scoping 101.3, 108.2, 1001.1 Seating, fixed 1009.1, 1030 Special amusement areas 411.4 Stages 410.2.3, 410.5 Stairways 403.5, 404.6, 1005.3.1, 1011, 1019, 1023, 1027 Temporary structures 3103.4 Travel distance (see Travel Distance) 1006.2.1,

    1017

    Turnstile 1010.5

    Underground buildings 405.5.1, 405.7 Width 1005.1, 1005.2, 1005.4, 1011.2, 1012.5.1, 1020.3, 1030.6, 1030.8 Mechanical (see Air Conditioning, Heating, Refrigeration and Ventilation) 101.4.2 Access 1011.12, 1208.4 Air transfer openings 705.11, 706.11, 707.10, 708.9, 709.8, 712.1.6, 713.10, 714.1.1, 717 Chimneys (see Chimneys) Code Chapter 28 Disconnected 3303.6

    Ducts 704.7, 705.11, 706.11, 707.10, 708.9, 709.8, 710.8, 712.1.10.3, 712.1.6, 713.10, 714.1.1, 717 Encroachment, public right-of-way 3202.3.2 Equipment on roof 1511 Equipment platforms 505.3 Fireplaces 2111 Incidental use room Table 509.1

    Motion picture projection room 409.3 Permit required 105.1, 105.2 Roof access 1011.12 Seismic inspection and testing 1704.3.2, 1705.13.7 Smoke control system 909 Systems Chapter 28 Mechanically Laminated Decking 2304.9.3 Medical Care (see Institutional I-2) 407.1 Medical Gas Systems 427 Membrane Roof Coverings 1507.11, 1507.12, 1507.13 Membrane Structures 2702.2, 3102 Mercantile Occupancy (Group M) 309 Accessible Chapter 11B Alarm and detection 907.2.6.3.4

    Area 503, 505, 506, 507, 508 Covered and open mall buildings 402 Hazardous material display and storage 414.2.5 Height 503, 504, 505, 508 Incidental uses 509

Frequently asked questions

Do I have to recalculate every roof member when I move a building?

Yes — if the new site has a higher design snow load, you must verify members for the new loads. Only elements whose stress increase is ≤ 5% may be left unaltered under § 1402.5.

How do I know the “previous” site's snow load for comparison?

Use the design snow load that governed the building at its previous location (the values used at original design or the applicable code at that time). Where there’s uncertainty, document the basis and consult the AHJ (authority having jurisdiction) and a design professional. The CEBC compares the new-location snow loads to those at the previous location in § 1402.5.

If only a small portion of the roof is affected (e.g., new drift next to an addition), does the 5% exception still apply?

The CEBC’s 5% allowance is phrased element-by-element. However, drift and accumulation effects can concentrate loads and change which elements exceed 5%. Evaluate elements with the appropriate snow-drift provisions from the CBC/CRC when determining applicability.

Who can determine whether an element’s stress increase is ≤ 5%?

A licensed structural engineer or architect should perform the structural analysis and document the stress comparisons and any upgrades needed to comply with the CEBC § 1402.5.

Are there other thresholds for wind or seismic when relocating a building?

Yes — the CEBC sets different thresholds and exceptions for wind and seismic load comparisons in § 1402.3 and § 1402.4, respectively; don’t assume the same numeric rule applies.

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