A report on the condition of the Centennial Arena was delivered to the Recreation and Culture Committee yesterday by Dr. Dan Tingley and Dr. Omar Abdelkarim of Wood Research and Development (WRD).
Tingley is the global Structural Engineer of Record and Abdelkarim is the Canadian Senior Engineer at WRD.
“We’re working with five different arenas right now in Canada, built between 1952 and 1972. And these sorts of issues become pretty common when you let moisture get into the building,” Tingley told the committee.
He also told the committee that besides a leaking roof, the HVAC system was inadequate, noting the increase in moisture content in timbers the further away they were from the HVAC equipment.
"People don't often think you need an air handling system in a hockey arena, but it's a dynamic environment. Timber does really well in swimming pools and any place with moisture, but [...] it doesn't do well with ambient water. I mean, there's a difference between being over a swimming pool [compared to] having a leaking roof saturate near constantly. There's a big difference," Tingley said.
The arena structure inspection is continuing. In addition to visual inspections and measurements, non-destructive stress wave timing methods were used to determine the condition of the wood structure. “It’s a non-destructive way of doing a lot of measurements in a hurry versus the old ways of drilling holes in.” Tingley and Abdelkarim brought a small sample of wood removed from the arena structure and demonstrated the instrument.
Tingley told the committee that the structural issues were mainly due to “significant [roof] leaking over a prolonged period.” He also noted that since his inspection five years ago, “critical elements in the trusses and columns had decayed in areas that were previously acceptable.”
It was when these conditions were noted, that the arena was closed in September for public safety.
Commenting about pictures in his presentation, he said, “These are pictures that show you the tremendous extent of the moisture flow-through of that roof. The roof leaks excessively.”
They also noted design deficiencies from long ago. Most arena roofs have a plywood deck sheathing installed. Centennial Arena does not. Plywood decking adds rigidity to the overall structure, a point Tingley mentioned multiple times, noting that a flexing building will be a leaking building.
He also mentioned that at one end of the building, the purlins were undersized. Purlins support the trusses, holding them straight and in position. Referring to a photograph, Tingley pointed out how the lack of support resulted in deformation of one of the trusses.
Commenting about the deformed truss, he said, “Well, if there’s blame, it goes right back to ’68 because that’s the time that there should have been more lateral support installed.
But Tingley had encouraging information to share too. “One of the things I’ll tell you about this building is there’s a lot more right about it than wrong.” And he pointed to the diagrams showing where concerns were marked in colour. “If you look at these sketches, you’ll notice something. Just a few reds and yellows.”
“But the important thing to note, as we continue to look through these, is that you’ll notice there’s very few in terms of the total amount of data that we’ve gathered here. There’s very few reds and yellows.”
The long service life of maintained wood was a point Tingley made clear at the beginning of his presentation, “I want to make a few things very clear. Wood does not have a ‘use by’ date. I’ll say that again: Wood does not have a ‘use by’ date.”
“I just finished a design and solution for Unity, Saskatchewan, for their curling rink in their hockey arena. It had a failed rafter in it. It was built in ’62. They asked me how long it would go for, and I said, 'Well if you maintain it and look after it, it’ll go another 50 years.' There’s no limitation.”
When the presentation was complete, Committee Chair Rick Bull, opened the discussion for comments and questions.
Councillor Norman Mann commented, “Dr. Tingley, thank you for your brutal honesty today. I truly appreciate that. I think some of your comments should be echoed throughout the community about the necessity of closing the facility. It was not done as a whim or a lark.”
“I think there’s some optimism that you’re showing tonight, but we’re clearly not out of the woods yet, but I look forward to the conclusion of the report and beginning some final decisions on the facility,” Mann said.
Later in the discussion, Acting Director of Public Works, Bill Goulding, commented, “At the end of the day, we’re still at a point where it’s a relatively economical structure compared to replacement.”
“There’s nothing that we found in the last two weeks that has swayed that perception.” Goulding added, “I would be very surprised if we found another major element that was of considerable concern, that would swing this away from a repair scope of work.”
Describing cost estimates at this stage as a "'D' estimate", Tingley cited examples he has seen of restoration cost versus replacement cost.
"I can tell you from having done this for a long time in my career and many buildings. In Penticton, for example, a Memorial arena was built in 1954. The council decided to tear it down, but before they did, they wanted to inspect it just to see if they could keep it for a practice arena for a couple of years. While they built their other arena. We inspected that and the restoration cost them about 400,000. That's still going today, 20 years later."
"The Chester Arena in Nova Scotia was built in 1962. They just embarked upon a restoration there. The cost of that restoration is 2.5 million for the curling rink and the hockey rink together. The cost of replacement for them is 16.5 million."
"So when you talk about restoring an old timber structure, traditionally the cost is a fraction of new, as in, usually, a 10th to an 8th. That's the usual numbers," he said.
Tingley: “I can tell you [that] what you folks are facing is no different than your counterparts everywhere else. They’re facing tight budgets, constrictions of that nature. There’s just not the money there used to be to build a new building. Restoring the old is usually the way forward.
Committee Chair Bull acknowledged the work of staff in recent weeks and thanked them. “I’d also like to thank the staff that’s been doing all the remedial work. I believe they’ve been working six days a week with twelve-hour shifts for the last two weeks to get this done so that WRD can get in and do their assessments.
“So, without them, we wouldn’t be getting this far. So, thank you to the staff that are doing all that.”
The inspection work is planned to continue with final plans for temporary shoring and supporting to be completed and implemented.
The near-term aim is a stable building and a repair design suitable for tender.
"I think that the best way forward for that building is the proper design that restores it to bring it up to service," Tingley said.