Beneath the shadow of the landmark Halifax Citadel, work is underway on the largest healthcare infrastructure project in Atlantic Canada’s history.

The Halifax Infirmary Expansion Project (HIEP) includes a 14-story tower that will house operating rooms, an intensive care unit and an emergency department twice the size of the current facility.

Given the project’s height and its large footprint, it became clear early in planning that multiple cranes would be required to efficiently move construction materials round the massive site.

When it comes to construction tower cranes, there are several options, but they generally fall under two categories: freestanding and tied-in or braced cranes. 

For multifloor, high-rise construction, tied-in cranes are more common because they can reach greater heights. They use the structures themselves for support, and their heights are increased or “climbed” as new floors are added to the project. However, the climbing process takes time and incurs extra costs. Those expenses and associated schedule risks were key considerations for the publicly funded project where predictability and continuity of work were critical.

“Another challenge with jacking a crane is that the building envelope is compromised when the tower crane is tied in,” says Warren Tutton, senior manager for construction engineering at PCL. “Also, it’s critically weather-dependent, and jacking usually happens on weekends, when other work is not happening. If the wind picks up, we have to postpone the operation — so there is a scheduling risk if we miss one of those weekends.”

Freestanding cranes, on the other hand, allow more flexibility because they can be brought up to their maximum height right away, and can reach across entire horizontal areas and vertical heights without being blocked by tie-ins. 

In this case, with a need for four cranes in a tight urban space, an aggressive schedule, and a sealed hospital construction site, Field Operations Manager Michael Halajian weighed the options, and decided freestanding tower cranes were the best option.

“I’m always looking at whether I can freestand these,” says Halajian. “In this case, with so many moving parts, it was cost effective. We found there was more value and less risk for us and for our client than tying in.” 

The challenge was the height. With a 14-story tower and three other cranes, the highest — known on the site as TC1 — had to go higher than freestanding cranes normally reach.

Before this project, the tallest freestanding crane PCL had ever erected was 100.3 meters, during construction of the Arthur J.E. Child Comprehensive Cancer Centre in Calgary, between 2017 and 2022. 

The Nova Scotia project required a crane to stand 105 meters — a height made possible by using the tower crane manufacturer’s heavy mast sections along with its current generation of versatile tower cranes.

“They’re the largest and strongest mast components we’ve ever used, supporting a tower crane that exceeds the size and capabilities of our traditional fleet, and operating in a challenging environment at an unprecedented height,” explains Tutton.

“If you can freestand it, you do,” says Luke Skelhorn, a superintendent on the hospital project. “Not being tied in allowed us to get more work done more quickly.”

The new equipment presented opportunities, but also introduced new challenges. Because erecting a crane at this height was a first for PCL — and rare for the industry — there was no playbook or standard practice to follow.

The team had to design a custom foundation anchor using a nearly eight-foot-tall concrete slab, sandwiched between two massive steel plates, each weighing around 14,000 pounds.

“It’s a lot more complicated than a typical anchor stool,” says Brad Kelly, the superintendent who oversaw the installation of all four cranes. “TC1 had a significant level of additional reinforcement that the other three didn’t need. It’s more specialized and took a lot more time and effort for field management to coordinate.” 

That coordination involved multiple stakeholders, including engineering, erectors/installers, metal fabricators, material and equipment suppliers (both domestic and international) and the crane manufacturer.

The Halifax region’s erratic coastal weather was another factor that had to be included in the engineering equation, to ensure the safety of everyone on site and the public.

“They are in a different wind zone than most of North America, so we had to deal with significantly higher wind loads,” says Tutton. “As you know, some hurricane remnants can pass through there, so it's a risk that we had to evaluate.”

The team also faced an unexpected complication when it came to securing the European-built crane to the footing. Metric dimensions at the crane base didn’t align with the imperial measurements of the American-built threaded rods that connect the crane base to the anchor stool.

“The solution required increasing the hole size by just a couple of millimeters,” says Keith Donnelly, a superintendent responsible for carrying out the plan to erect TC1. “So it’s a very small amount, but we had to get approval from the crane manufacturer in Germany, to ensure the North American steel rods could be installed, so there was quite a bit of back-and-forth, and thankfully it all worked out.”

“This really showcased PCL's ability to handle complex challenges like this,” says Kelly. “I don’t think many general contractors would have the capability to even entertain these challenges, whereas we look at this, tackle it, and immediately find a solution that translates into reduced risk and greater confidence for clients on large-scale projects like this. I think that really says a lot about what PCL can do as a leader in this industry.”  

With the major challenges now in the rearview mirror, all four on-site cranes are working smoothly on the hospital project, and PCL’s top crane experts believe this work will pave the way to increased use of taller freestanding cranes, with fewer challenges.

“Now that our teams have access to freestanding at greater heights, I expect we’ll continue to do so, taking advantage of the benefits on future projects,” says Halajian.   

The benefits for PCL and its partners: greater schedule certainty, fewer shutdowns, less disruption to the construction site and surrounding area — and an improved ability to seal portions of the structure earlier.

For the team in Halifax, the pride goes beyond reaching industry-leading heights to the lasting impact this hospital will have on the community where they live and work.

“I’ve got two young kids, and it means a lot to be part of this,” says Donnelly. “It’s going to last for many years and generations. It’s going to mean a lot to the people of this province.”

“I can’t wait until we cut the ribbon on opening day,” says Kelly. “At the end of the day, we know that we’re building a state-of-the-art facility for our families and for our community.”