If the building meets all of the following criteria, Part 9 seismic compliance can be presented to the CVRD Building Inspector for review with your Building Permit Application:

• • Wood-framed walls supporting a roof and no more than 2 floors of normal weight construction (for normal weight and heavyweight construction definitions, see the BC Housing Illustrated Guide: Lateral Bracing Requirements – Part 9 of the BC Building Code 2024)
  • Wall heights under 3.1m within Braced Wall Panels,
  • Roof and wall planes are clad, sheathed or braced on at least one side,
  • The small repetitive structural members are spaced not more than 600 mm o.c.,
  • The constructions do not serve as foundations,
  • The specified live load on supported subfloors and floor framing does not exceed 2.4 kPa, and
  • The span of any structural member does not exceed 12.20 m.

No. The 2024 BCBC requires Braced Wall Bands and Panels under Part 9 design. A post and beam structure requires design and oversight by a Registered Professional under Part 4 of the 2024 BCBC.

No. Under the 2018 BCBC, there was an exemption for single storey residential Accessory Buildings that met certain criteria. The 2024 BCBC does not provide that exemption unless a Geotechnical Engineer has determined your Site Class, and your Smax has been calculated to be below 1.2.

Please note that under the new 2024 BCBC seismic provisions, the “Additional System Considerations” are no longer permitted in areas with an Smax over 1.2. Single storey accessory buildings, garage front wall, porch roof, etc. exemptions are no longer available unless the Smax is below 1.2. ALL Electoral Areas within the CVRD have an Smax over 1.2 (at Site Class C), however, Smax may be determined by a Professional Geotechnical Engineer and may be lower than 1.2, however, this is not guaranteed, and is site and soil specific.

Due to the Smax values in the CVRD, only the Part 9 Calculation Method or the Alternative Calculation Method may be used (Simplified Method is not permitted).

Part 9 Seismic Designs must clearly illustrate ALL of the following:

• Site Class (as determined by a Geotechnical Engineer or use Site Class E/Unknown from the CVRD Climatic Data for your area) and Smax values must be provided
• Calculations must be shown to obtain the percentages of Braced Wall Panels within each Braced Wall Band
• Floor Plan views showing Braced Wall Bands and Panels
• Referencing framing type(s) being proposed and locations
• Anchor bolt size and spacing
• Fastener size and spacing
• Roof eave to ridge height
• Attachment to roof framing or trusses
  • It is recommended that the seismic design and attachment be reviewed with the truss manufacturer prior to Building Permit Application.
• Braced Wall Bands must:
  • surround the perimeter of the building (including all decks, porch roofs, garage walls, etc.)
  • be full storey height,
  • be not more than 1.2 m wide,
  • lap at both ends with another braced wall band,
  • be aligned with braced wall bands on storeys above and below, and,
  • conform to the spacing and dimensions given in 2024 BCBC Table 9.23.13.5. and Article 9.23.13.7

Part 4 Structural Design is under Division B Acceptable Solutions of the BC Building Code where Article 2.2.1.2 Structural Design states “For design carried out in accordance with Part 4 of Division B, the designer shall be a registered professional skilled in the work concerned.”

This involves having the building designed and reviewed per the requirements of Part 4 Structural Design of the 2024 BCBC by a registered professional (usually a structural engineer) instead of the prescriptive requirements of Part 9. This requires that an engineer be retained for the project who will provide sealed structural drawings accompanied by a Letter of Assurance (Schedule B) for your building permit application.

This option provides significantly greater flexibility in building design than the Part 9 requirements (such as post and beam connections, tall walls/high ceilings, designs beyond ‘repetitive framing members,’ large openings/glazing, and more).

The structural engineer then performs Field Reviews to inspect the construction of the building and confirm that it is being constructed per their design and specifications. At the end of the project and when they have confirmed the final building meets all of their design and specification requirements, the engineer will provide a final Letter of Assurance (Schedule C-B) which is required for Final inspection/Occupancy.

Building Permit Applications where a registered professional has provided a sealed design and Letter of Assurance may be subject to a discount on permit fees per section 743 of the Local Government Act.

1. Review the CVRD Climatic and Seismic Data sheet and use Site Class Unknown (E) Smax value based on your approximate location (or Site Class can be determined by a Geotechnical Engineer and a sealed memo can be provided to the CVRD stating their findings).
2. Use the Natural Resources Canada – Earthquakes Canada 2020 National Building Code of Canada Seismic Hazard Tool to calculate the specific locations’ Smax value based on Site Class Unknown (E) or Site Class as determined by your Geotechnical Engineer:
   1. Go to the 2020 National Building Code of Canada Seismic Hazard Tool
   2. Select “Site Class (Xs)” as the site designation.
   3. Select the appropriate Site Class (A, B, C, D or E). **Site Class is determined by a Geotechnical Engineer, if you do not have Site Class specified by a Geotech, you must use Site Class Unknown which is E.
   4. Enter the latitude and longitude of the site’s location manually, or determine the latitude and longitude from an address or current location.
   5. Click “Obtain Seismic Hazard Values” The following values are needed to determine Smax: Sa(0.2,XS) and Sa(0.5,XS).
   6. Determine S(0.2,XS) in accordance with Sentence 4.1.8.4.(6): S(0.2,XS) = Sa(0.2,XS) or Sa(0.5,XS), whichever is greater
   7. Determine S(0.5,XS) in accordance with Sentence 4.1.8.4.(6): S(0.5,XS) = Sa(0.5,XS)
   8. Determine Smax: Smax = (2/3)S(0.2,XS) or S(0.5,XS), whichever is greater
   9. Round Smax to three significant digits.

• Information Bulletin: Transition period for seismic requirements in the
  British Columbia Building Code 2024
• Illustrated Guide: Lateral Bracing Requirements – Part 9 of the BC Building Code
• Canadian Wood Council Wind and Seismic Bracing Calculator
• Natural Resources Canada – Earthquakes Canada: 2020 National Building Code of Canada Seismic Hazard Tool
• 2025 CVRD Climatic and Seismic Data
• 2024 BC Building Code