CASE STUDY
144-UNIT
TOWNHOUSE
Comprehensive structural design for a large-scale wood-frame townhouse complex including foundation systems, shear walls, and gravity load analysis across 144 residential units.
CASE STUDY
144-UNITTOWNHOUSE
Comprehensive structural design for a large-scale wood-frame townhouse complex including foundation systems, shear walls, and gravity load analysis across 144 residential units.
PROJECT OVERVIEW
This project involved complete structural engineering for a 144-unit wood-frame townhouse development in Burnaby, BC. The complex consisted of multiple connected building blocks, each requiring individual gravity load design, shear wall layouts, and foundation systems coordinated across a challenging sloped site.
Zagrosia Engineering provided full structural design services from preliminary layout through permit submission and construction administration. Close coordination with the project architect ensured shear wall locations were integrated into the architectural plan without compromising suite layouts or common corridor widths.
PROJECT DETAILS
- LocationBurnaby, BC
- Building TypeMulti-Family Residential (Wood Frame)
- ServicesStructural Design & Shear Wall Engineering
- JurisdictionCity of Burnaby
- CodeNBCC 2020 / BCBC 2018
- ExpertiseP.Eng — British Columbia
THE CHALLENGE
Designing lateral shear wall systems across 144 units required careful distribution of seismic and wind loads among dozens of individual shear walls. The architectural floor plans limited wall placement, requiring iterative optimization of shear wall lengths, locations, and hold-down anchorage to meet code drift limits.
The sloped site introduced differential foundation elevations across the complex, requiring stepped foundations and retaining wall design at grade transitions. Drainage and waterproofing coordination at the foundation level was critical to prevent moisture intrusion in below-grade storage areas.
ENGINEERING APPROACH
Gravity Load Design
Floor joist, beam, and post systems designed for each unit type under NBCC 2020 dead and live load combinations, including balcony and roof snow loads specific to Burnaby's snow zone.
Shear Wall Layout
Lateral load distribution analysis performed for wind and seismic demands. Shear wall lengths, nailing schedules, and hold-down connector sizes optimized for each building block.
Foundation Design
Strip footings and grade beams designed for the site's varying soil bearing conditions. Stepped foundations and retaining elements detailed for the sloped portions of the site.
SCOPE OF WORK
Floor & Roof Framing Design
Complete gravity framing design including joists, beams, headers, and posts for all 144 units
Shear Wall Engineering
Lateral load analysis and shear wall schedule development for seismic and wind resistance
Hold-Down & Connector Design
Sizing of all hold-down anchors, Simpson connectors, and strap ties for shear wall uplift demands
Foundation Design
Continuous footing and grade beam design coordinated with geotechnical report soil parameters
Permit Drawing Set
Full structural drawings and calculations for City of Burnaby building permit submission
OUTCOME
PERMITTED & BUILT ON SCHEDULE
The 144-unit townhouse complex received structural permit approval from the City of Burnaby with no major revisions required. All building blocks passed structural inspection, and the project was delivered within the construction program timeline. The shear wall system performed within allowable drift limits under peer review.
START YOUR PROJECT
DO YOU WANT TO START YOUR PROJECT?
Every project is unique. Contact us to discuss your specific requirements, and discover how we can help.
DO YOU WANT TO START YOUR PROJECT?
Every project is unique. Contact us to discuss your specific requirements, and discover how we can help.