Residential Addition Structural Design – Elmira
This project involved the structural design for a residential addition, including new basement and ground-floor framing, foundation tie-ins, and opening supports.
Parsways prepared structural drawings for the addition, coordinating the new work with existing foundation walls, floor framing, roof loading, and Ontario Building Code 2024 requirements.
Location: Elmira, Ontario
Completion: May 2026
Sector: Residential
1. The Challenge
The addition required new structural framing and foundation work to connect with the existing house without undermining the existing foundation.
Existing Foundation Interface:
The drawings required field verification of the existing foundation depth and footing size before excavation.
Load Path Coordination:
New beams, joists, bearing walls, headers, and posts had to maintain a continuous load path from roof and floor framing to foundation.
Openings and Masonry Support:
New window and door openings required structural headers, loose steel lintels, and full bearing coordination with the architectural drawings.
2. The Engineering Solution
Parsways designed a code-aligned structural package for the residential addition using OBC 2024, CSA standards, and Waterloo climatic loading data.
a) Foundation and Basement Framing:
The design included 10-inch reinforced concrete foundation walls on 20-inch by 8-inch strip footings, tied into the existing foundation with dowels and waterstop detailing.
b) Wood and LVL Framing:
New 2x10 floor joists, LVL flush beams, joist hangers, trimmer joists, and bearing walls were specified to support the basement and ground-floor addition.
c) Headers and Lintels:
Exterior wood headers and galvanized loose steel lintels were sized for new openings, with bearing, fastening, and corrosion-protection requirements clearly noted.
3. The Outcome
The project resulted in a permit-ready structural design for a residential addition, with clear foundation, framing, header, and lintel details. The design helped connect the new addition to the existing structure, reduce construction uncertainty during excavation, and support long-term stability in accordance with OBC 2024 and applicable CSA requirements.