By Bruce Nagy
Built in the 1970s, Montreal’s Olympic Stadium has a special place in history as the most over-budget white elephant project in the world, according to a 2014 report in archdaily.com. During construction its $148 million budget rose to $264 million by the time it opened, uncompleted, for the 1976 Summer Olympics. When it was finally paid off in 2006, the stadium had cost the city $1.61 billion.
Meanwhile, in the construction industry, there’s a growing gap between large, successful, efficient companies and those that are being forced to sell or close. The future will favour efficiency, planning and communication between parties, 3D modeling and building information modeling (BIM) and more accountability in construction contracts. Design-build firms may also have some advantages.
Rapid and efficient construction
“There were many doubters that we would be in the building in the fall of 2016, when the architects started in 2013,” reported Svetan Veliov, lead mechanical engineer for the new Bergeron Centre for Engineering Excellence at York University in Toronto. “But construction was less than 18 months. And to meet that schedule would have been impossible without BIM,” added Veliov, from the Toronto office of Arup, an international firm of consulting engineers. The company has been a leader in BIM and wanted to use the new engineering school as a showcase for its advantages.
It wouldn’t be easy. The project sought Leadership in Energy and Environmental Design (LEED) Silver certification while requiring numerous high-tech spaces with nasty emissions, along with a structurally isolated, heavily reinforced lab for materials destruction testing, and a formidable below grade challenge.
There was a one-metre diameter storm sewer cutting diagonally through the building site, sloping into over-capacity storm-drainage facilities. “We designed around it and left it abandoned in place, because to remove it would have eaten up three or four months in our schedule. That’s why the precision of 3D modelling became critical,” said Veliov.
Mechanical systems were to include demand control ventilation, variable speed fans and pumps. The lab exhaust system would use high efficiency fans and motors and a heat recovery system for 100 percent of the make-up heating load in winter.
Heat was to come from the university’s central steam plant, via heat exchangers for radiant ceiling panels, plus perimeter trench heaters below double and triple-height glazing. The campus chilled water plant would also supply cooling, with a dry cooler at roof level for data, electrical room and lab processes.
The building would include a clean room rated at ISO Class 7 with its own air handling plant and three environmental chambers with individualized temperature control (-35°C to 85ºC) for experiments. There would also be a spray paint booth, located at the roof level, with a dedicated filtration exhaust and make-up air system; and an extensive green roof and underground infiltration system to promote on-site rainfall retention and groundwater recharge.
The mechanical systems were to be partly exposed as learning and teaching tools for engineering students and faculty. In the offices, monitors, lamps and other devices would shut off when rooms were unoccupied.
Prefabrication saved time
Using BIM helped avoid underground clashes as the sub-trade contractor used the Arup model to generate an off-site materials takeoff and prefabrication. Materials were individually tagged, cut to measure and delivered to the site in crates, which reduced a two-week installation to three days. The same method was then used for piping, ductwork and conduit.
The university, the architect, the construction manager, the engineers and sub-trades all used the same BIM model. “Working in the model alongside the other contractors was like working in one big office. A mechanical designer might amend the model and we could then accept the changes almost in real time,” said Veliov.
“It’s a very technical building, jam packed with labs and equipment, but it’s still a beautiful building,” remarked Troy White, BIM lead at Arup Canada. “In the past we’d wait for the architects and were not included until the design was about 33 percent complete, then the rooms would grow smaller, and the ceilings lower until you didn’t have a beautiful building. By using BIM at the very early stages, we were already doing hydronic, pressure and HVAC calculations, making everything more efficient, more accurate, and more holistic. We’re coordinating shafts and the mechanical room, and we can maintain a slim service sandwich.”
According to Autodesk, a BIM vendor, “Poor use of data coupled with highly fragmented teams,” is costing U.S. building owners about $16 billion each year and 30 percent of construction work is rework.”
Delays, claims, litigation and RFIs are all becoming too expensive in construction. Advocates suggest that some level of BIM is taking over new construction, even for houses, and will soon be much more widely used in Canada.
Meanwhile, in Montreal
So what happened to the big white elephant in Montreal? In 2013 the city began a series of major upgrades to Olympic Stadium. But this time it was different. It’s not over budget or late. An ironclad contract based on guaranteed energy savings and a nimble design-build mechanical firm did the trick.
They needed $15 million to convert the stadium’s old steam system to hot water, plus new heat recovery chillers, new variable speed pumps and digital, rather than pneumatic controls. They also wanted to update the lighting. From the beginning they knew there would be little public appetite for pouring much more money into a 40 year-old stadium with a dark history, where even the city’s CFL team doesn’t play. But “guaranteed energy savings” and some clean-tech incentives could make a difference, and they ultimately made the project possible.
Operations and energy manager Dominic Desjardins said they were not accustomed to this kind of procurement agreement. “We brought in a third party consultant who evaluated potential savings to help build our RFP document. All the bidders agreed on a baseline year… Preparing the RFP took longer than the upgrade itself.”
Simon Verville, mechanical engineer for Ecosystem, Quebec City, the design-build firm that won the bid, says that the structure of the agreement brought many benefits. “We are motivated to continually optimize the system over the 20-year term, because the more energy savings we find, the more it benefits us financially.”
The company has a full-time engineer working on site, although this may not always be necessary, given that the sophisticated Johnston Controls system integrates all of the equipment through 20,000-22,000 control points. Everyone who has clearance can access it online. “If something breaks, you just fix it immediately. There is no legal consideration of fault or responsibility,” he noted.
Desjardins reported that the actual energy savings seem to be closer to $1.5M per year than the $1.3 required under the agreement. There are also maintenance savings, because the boilers don’t run in the summer and the elimination of steam reduces the need for an on-site engineer.
Things are now much better at the Big O. They have nearly forgotten that night in 1998 when part of the roof fell on the Subaru exhibit at the auto show. It still hosts the auto show, home show, Women’s FIFA Soccer, some Blue Jays games, motocross and AC/DC concerts. And who knows, one day, the Alouettes?
And, thanks in part to the unique contract that pays for energy savings over the baseline for 20 years, the engineers are making money too. More and more, a progressive approach to ICI construction is paying off.