In defence of tiebacks: Lyall

By Richard Lyall

for Canadian Contractor

March 12, 2026

Ontario is in the midst of a housing crisis and governments at every level have committed to increasing supply, speeding up approvals, and reducing unnecessary costs that make new homes less attainable.

However, against this backdrop, proposals have been put forward to ban construction tiebacks in several municipalities - including the City of Toronto. If implemented, this would represent a deeply troubling and counterproductive - not to mention costly step backwards for Ontario.

Tiebacks are not an experimental technique. They are a state-of-the-art, widely accepted engineering practice used to support deep excavations during high-rise construction.

In the Greater Toronto Area alone, more than two million tiebacks have been safely installed since the 1970s. They are governed by rigorous engineering standards and are routinely used to protect streets, utilities, neighbouring buildings, and - most importantly - workers.

A new report released by RESCON and the Ontario Association of Foundation Specialists in partnership with the Residential and Civil Construction Alliance of Ontario makes the implications of a ban unmistakably clear.

The report compared tiebacks with the primary alternative: internal steel bracing. The findings are stark.

In a representative high-rise residential project, replacing tiebacks with internal steel bracing would add an estimated $5 to $6.5 million in costs - or roughly $14,000 to $18,000 per unit. At a time when affordability is already stretched to the breaking point, this kind of regulatory burden is indefensible.

Those costs would not be absorbed by developers. They would be passed directly to buyers and renters, further eroding affordability and undermining the province’s housing supply objectives.

But the financial cost is only part of the problem.

Internal steel bracing systems clutter construction sites, restricting movement within excavations and complicating forming and concrete work. The result? Slower builds and extended disruption.

The report estimates excavation and forming timelines would increase by five to seven months if tiebacks were banned. That means longer road closures, prolonged lane reductions, extended noise, and increased congestion around already busy urban sites.

Ironically, a policy ostensibly introduced in the name of safety could create new safety challenges. Congested excavation sites with bulky steel frames limit maneuverability, complicate sequencing, and introduce additional hazards for workers.

Tiebacks, by contrast, free up the excavation area. They allow concurrent construction activities and improve site logistics.

The Ontario construction industry has built up more than 50 years of expertise, specialized equipment, and trained trades around their safe use. Forcing a sudden shift away from this established system would require costly retooling across the industry.

The push to restrict or ban tiebacks stems largely from a 2022 incident in Toronto, when a sewer tunnel boring machine encountered old tiebacks in the west end. Subsequent analysis indicates the issue arose from a municipal administrative clerical error: incomplete records were provided to the tunnelling consultant or contractor.

In other words, the problem was not the technology itself - it was documentation and co-ordination.

The appropriate response to an administrative failure is to fix the administrative process. Improved record-keeping, better data sharing, and clearer protocols for identifying legacy tiebacks would address the underlying issue without dismantling a proven engineering practice.

Banning tiebacks because of a clerical oversight is akin to banning elevators because of a maintenance error. It is an overreaction that solves the wrong problem while creating many new ones.

Ontario’s housing targets are ambitious and meeting them will require innovation, efficiency, and regulatory discipline - not policy shifts that inject millions of dollars in new costs into every high-rise development.

Continued acceptance of tiebacks, particularly within municipal rights-of-way, supports faster project delivery, reduced congestion, and more economical construction. Restricting or banning them would make marginal projects unviable and discourage investment at precisely the moment we need it most.

Tiebacks are safe, effective, efficient, and proven. They are integral to how modern high-rise construction is delivered in Ontario.

RESCON and our industry partners are engaging municipal and provincial leaders to ensure they understand the real-world implications of this proposal. Policymakers deserve clear, evidence-based information about the cost, safety, and supply impacts of regulatory decisions.

The message from our industry is straightforward: if it isn’t broken, don’t ban it.

Tiebacks have served Ontario well for decades. Abandoning them now would raise costs, slow construction, increase congestion, and undermine housing affordability - all without improving safety.

Richard Lyall is president of the Residential Construction Council of Ontario (RESCON). He has represented the building industry in Ontario since 1991. Contact him at media@rescon.com.