Speed, Safety, and Single Responsibility
Why Mid-Rise and Multiplex Developers Are Turning to Cold-Formed Steel
Ontario’s building codes are changing. So are developer expectations. Prefabricated cold-formed steel isn’t just safer — it’s faster, smarter, and more profitable.
1. A New Reality for Ontario’s Builders
Across Ontario, mid-rise and multiplex construction is on the rise — literally.
Cities are densifying, housing demand is growing, and developers are under pressure to deliver faster, safer, and more efficient buildings.
But the game has changed.
Ontario’s Building Code now requires fire-rated, non-combustible assemblies for shared or exterior walls in multi-unit buildings.
That means one thing:
The age of wood-framed multiplexes is ending.
Enter Cold-Formed Steel (CFS) a material and system built for this exact moment.
At LEFF, we design, engineer, and prefabricate complete CFS structures ready for rapid on-site assembly compliant with Ontario code, resistant to fire, and optimized for speed and profitability.
2. The Code Is Clear | Fire Resistance Is No Longer Optional
Ontario’s Building Code (Part 3 & Part 9) defines strict requirements for fire separation between dwelling units and non-combustible exterior walls in multi-residential projects.
For developers, this means:
- Shared walls (between suites) must be non-combustible and fire-rated.
- Exterior walls in most mid-rise buildings cannot be wood-framed.
- Buildings must demonstrate tested, rated assemblies that prevent flame spread.
Cold-formed steel framing inherently meets these demands.
It’s non-combustible, dimensionally stable, and can be combined with UL/ASTM-rated assemblies for 1–2 hour fire protection.
No coatings. No treatments. Just performance by design.