Building
Information
BURNABY PLANNING AND BUILDING DEPARTMENT
Structural Design to resist Lateral Loads
for Single and Two Family Dwellings
The purpose of this brochure is to inform owners, designers, engineers and
contractors of the structural design requirements to resist lateral loads due to
wind and earthquake for the submission of building permit applications for single
and two family dwellings.
“This information is provided for convenience only and is not in substitution of applicable City Bylaws or Provincial
or Federal Codes or laws. You must satisfy yourself that any existing or proposed construction or other works
complies with such Bylaws, Codes or other laws."
Effective immediately, permit applications with structural drawings that fail to comply
with the requirements specified in this brochure will not be accepted. Please ensure all
the required information is on the drawings prior to making the application in order to
avoid unnecessary delay in the issuance of permits.
Quality of Structural Drawings

Hand-written structural notations will not be accepted. All structural notations
shall be legible and of good drafting quality.

We may ask the structural drawings to be separated from the architectural
drawings if the combined structural and architectural drawings are not legible.

Notes and details on separate sheets (of different sizes) attached to the
structural drawings are not acceptable. All notes and details shall be on the
structural drawings.

If revisions are needed, two complete sets of revised drawings (signed, sealed
and dated) by the structural engineer are required. At the discretion of the plan
checkers, minor revisions may be done by hand by the structural engineer with
his/her initials on the original submitted drawings. We will not accept “cut and
paste” sheets.
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Structural Design to Resist Lateral Loads
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Revised: 2014 October 09
Information on Structural Drawings
To demonstrate code compliance, the following must be shown on the structural
drawings.

The 2012 BC Building Code (BCBC) requires all Part 9 buildings, including single
and two family dwellings, to be designed to resist lateral loads due to wind and
earthquake using ONE of the following methods:
o
Part 9 (9.23.13.) of the 2012 BC Building Code, or
o
Part B or Part C of “Engineering Guide for Wood Frame Construction 2009 Edition”
(CWC 2009) published by the Canadian Wood Council, or
o
Part 4 of the 2012 BC Building Code
The structural engineer must indicate the code compliance option used for the design
for lateral loads using the following statement. If CWC 2009 is used it must be stated if
Part B or Part C is used.
I,_______________________________________, have reviewed and confirmed
that the lateral resistance of this building for wind and earthquake is designed
in accordance with_____________________________.

General structural notes must specify the requirements of the 2012 BCBC
applicable to the design, including but not limited to:
o
o
o
o
o
o

climatic loads, such as snow (Ss), rain (Sr), wind (q), seismic (Sa)
live loads – floors and roofs
dead loads of floors and roofs - indicate the types of material used, such as
roof tile, concrete topping, and others as applicable
dead loads of architectural components, such as stone cladding, chimneys,
canopies with unusual loading
specification and standards for sheathing, lumber, fasteners, steel
connectors, hold-downs and anchor bolts – where a standard specification is
applicable
assumed soil bearing capacity – reference the soil report if available
If Part 9 of 2012 BCBC or Part C of CWC 2009 is used to design for lateral loads
then the following must be shown on the structural drawings:
o
o
o
o
braced wall panels must be hatched and labelled BW
details of braced wall panels including framing, type of sheathing, size and
spacing of nails, blocking
percentage (%) of braced wall panels in each braced wall band at each floor
level
anchorage of braced wall panels including material, size and spacing
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Structural Design to Resist Lateral Loads
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Revised: 2014 October 09

If Part B of CWC 2009 or Part 4 of 2012 BCBC is used to design for lateral loads
then the following must be shown on the structural drawings:
o
o
o
o
o
o
assumed Site Classification
acceleration-based site coefficient, Fa
velocity-based site coefficient, Fv
ductility-related force modification factor Rd,
overstrength-related force modification factor, Ro
all shearwalls (those used to resist lateral forces and may include exterior
walls) must be hatched and labelled “SW”
o shearwall details including framing, type of sheathing, nailing size and
spacing, blocking
o details of all elements participating in the load path including drag struts,
hold-downs, straps, etc. to show how forces are transferred from roof to
foundation
Application of CWC 2009 and Part 4 of 2012 BCBC
The following are some examples of types of houses that MUST be designed in accordance
with Part B of CWC 2009 or Part 4 of 2012 BCBC:


heavy construction with both tile roof and concrete topping regardless of the number of
storeys
heavy construction with tile roof or concrete topping having more than two storeys of
wood-framed construction; including cripple exterior walls in the lowest floor
Structural Design using Part B or Part C of CWC 2009 or Part 4 of 2012 BCBC shall be carried
out by a Professional Engineer.
The entire Seismic Force Resisting System (SFRS) shall be designed using either Part C of
CWC 2009, Part B of CWC 2009 or Part 4 of BCBC 2012. Mixing and matching of these three
methods is not acceptable.
Renovations and Additions
All renovations and additions should be designed to the current 2012 BCBC, including the
lateral resistance to wind and earthquake loads. An existing home may not have the required
lateral load resistance. When an existing home is going through a major renovation or addition,
a Professional Engineer should be engaged to confirm that the addition or renovation does not
reduce the level of the structural performance of the existing structure below the level that
existed prior to the addition or renovation by using one of the four rational schemes as listed in
the “Guidelines for Professional Structural Engineering Services for Part 9 Buildings in British
Columbia” published by APEGBC. The structural drawings submitted for building permit must
indicate one of the scheme(s) used.
Some minor renovations and additions, such as new bathroom or new sundeck, may be
exempted from the above-mentioned requirements at the discretion of the plan checker/building
inspector. If you have any questions, please contact Plan Checking prior to making the permit
application.
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Structural Design to Resist Lateral Loads
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Revised: 2014 October 09
Seismic Upgrade of Existing Homes
There is no mandatory requirement to upgrade the structure of an existing home to resist
earthquake loads if the home is not going through renovations or additions. If the owner
chooses to do so, a building permit is required. The submission for building permit must comply
with all the requirements listed in this bulletin and all other applicable requirements as listed in
the brochures below.
Other Brochures related to this topic



Building Permit Application Requirements for Interior Finishing for Single and Two
Family Dwellings
Letters of Assurance for Single and Two Family Dwellings
Climatic information for Building Design in Burnaby
Good Engineering Practice
The Building Department may request the professional engineers to submit Structural Design
Calculations and/or confirmation of independent review as outlined in the Quality Management
Guidelines published by APEGBC to ensure the design is in compliance with the current B.C.
Building Code.
The Association of Professional Engineers and Geoscientists of BC (APEGBC) requires all
professional engineers to design in accordance with good engineering practice. In terms of Part
9 buildings, including single and two family dwellings, this means using the latest CWC as a
minimum. Further information can be obtained from the “Guidelines for Professional Structural
Engineering Services for Part 9 Buildings in British Columbia” published by APEGBC.
Structural drawings which do not meet the relevant code criteria for structural design will be
returned to the structural engineer for correction while the permit application is placed on hold.
Professional Engineers, who repeatedly submit incomplete or substandard design or failing to
comply with the above-mentioned “APEGBC Guidelines”, may be referred to APEGBC for
further action.
Field Reviews by Structural Engineer of Record
The Structural Engineer of Record must submit a field memo at sheathing inspection, framing
inspection and insulation inspection (if applicable) to confirm that the construction, including
braced walls/shearwalls, at that stage are constructed according to the drawings submitted for
building permit and is in general compliance with the B.C. Building Code. For further detail
please refer to our brochure “Letters of Assurance for Single and Two Family Dwellings”.
Further Information
Should you have any further questions please contact the Building Department at 604-2947130.
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Structural Design to Resist Lateral Loads
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Revised: 2014 October 09