Roofing a stadium

Dean-Chandler Roofing and Flynn Group of Companies team up to install a new roof system on Toronto’s Rogers Centre

The Rogers Centre in Toronto is the largest entertainment venue in Canada. Rock stars, musicians, artists and athletes have entertained audiences under the dome since June 3, 1989. Originally named SkyDome and renamed Rogers Centre in 2005, the world-class facility has been home to the Toronto Blue Jays since June 5, 1989. The stadium is known for many innovations that were ahead of its time such as a patented fully retractable roof, the first of its kind.

The retractable roof allows the venue to be an open-air facility with the ability to close during inclement weather. The system features a series of three moveable panels and one stationary panel that takes 25 minutes to open or close fully. The roof weighs 11,000 tons, and its highest point is 282 feet above field level.

Situated near Toronto’s CN Tower, the tallest freestanding structure in the western hemisphere according to World Atlas, falling ice was an issue for the Rogers Centre roof. Freezing rain and ice would build up on the concrete tower’s vertical surface, and when the weather warmed, the ice would fall on certain areas of Rogers Centre’s roof. In 2018, a massive ice chunk punched a hole through the entire roof assembly, including the structural metal deck.

As a result, a new 460,000-square-foot roof system had to be installed and completed within a 10-month timeline to accommodate the Toronto Blue Jays baseball schedule. Because of scheduling constraints and an urgent timeline, two roofing contracting companies were selected to work on the enormous project: Dean-Chandler Roofing Ltd., Scarborough, Ontario, one of the roofing contracting companies that installed the original roof system in 1987, and Flynn Group of Companies, Mississauga, Ontario.

"We were all pleased to work on Rogers Centre again. When we installed the first roof system, our lead foreman at the time, Joe Carneiro, was part of the team,” says Jay Campbell, vice president of Dean- Chandler Roofing. “Nearly 30 years later, his son was there with him to take part in the new roof system replacement, and they were our two foremen on the project.” (To read about other fathers and sons who work together in the roofing industry, see “It’s a family affair.”)

Safety and prep

In November 2018, Dean-Chandler Roofing and Flynn Group of Companies formed a joint venture partnership to share resources and meet requirements, each tackling a side of the roof. The roof system consisted of four panels: The Dean-Chandler Roofing team was tasked with replacing panels one (92,600 square feet) and two (15,900 square feet), and the Flynn Group of Companies crew worked on panels three (125,200 square feet) and four (88,300 square feet).

Because the roof surface was a dome shape, numerous months of preparation went into designing custom swing stages that were built and deployed at various drop zones from the center of the roof where workers would descend. The stages needed to conform to the slope and roof curvature as well as accommodate three workers, materials and equipment.

“The most unique aspect of this project was the leading-edge swing stage that cantilevered over the edge of the roof 25 stories above ground,” says Brad Noddle, project manager for Flynn Group of Companies. “As this swing stage was on the top peak of the roof, we were required to use another swing stage to pull us up to the leading-edge swing stage where we then descended to the dome to work. Site-specific and special swing-stage training was required to operate them.”

In some areas where swing stages were not a viable option for access, workers installed engineered ladders and planks to create safe work platforms as well as safety lines and additional anchors to accommodate the number of workers needed; existing lines also were recertified and used. All safety harnesses had to accommodate dual tie-off lines; the main line connected to the front of each harness. The stages and safety lines were inspected and logged daily before use.


The existing roof assembly consisted of 10-mil-thick polyethylene vapor retarder, mechanically fastened 2-inch-thick foil-faced polyisocyanurate insulation and 48-mil-thick Sarnafil® S327 PVC membrane fastened with Sarnabar® (U-shaped, roll-formed steel bars) on an acoustical metal deck. The Sarnabars were fastened with No. 11 Sarnafasteners.

A cover strip then was welded over each Sarnabar using Sarnamatic® welding machines. Eighteen-gauge triangular-shaped steel snow diverters were spaced every 24 feet vertically and fastened. The diverters were covered with 48-mil-thick Sarnafil G410 PVC membrane. A 3-inch overlap of the preadhered membrane was left on each side of the diverters to allow for heat-welding the laps with Sarnamatic welding machines.

The tear-off process was conducted in a few stages. The intent of the roofing project was to leave most of the existing vapor retarder and insulation in place, replacing only about 10% of the existing material. To accomplish this, a group of three workers ascended in a swing stage to a work area to cut the cover strip and unfasten and remove each Sarnabar. Then, they would descend, drop off debris at the base of the panel, and ascend again to remove existing membrane and replace wet or damaged steel deck, vapor retarder and insulation as needed.

At the base of each roof panel, the crews also removed 8 feet of the full roof system down to the steel roof deck, and in some areas, they replaced the steel decking as required. On panel one, the southern panel, there was an additional raised ledge that could not be accessed by a swing stage. For this area, workers removed the materials while being tied-off to lifelines and walked up the raised ledge.

Scaffolding and a ladder-and-plank system were installed in the corners of panel one to provide access to the extremely steep areas. The gutter area on panel one was the main staging area. On the building’s west side, workers used large disposal bins with castor wheels to remove debris from panels two, three and four and transported it to a gantry hoist that lowered the bins from the south end of the panel two gutter to the main concrete gutter at the base of panel one. From this gutter, workers placed the debris into bins and wheeled them down to the building’s south end where a hoisting platform was used to lower the bins to panel one’s lower gutter.

At this point, workers separated the membrane from other debris and rolled and tacked it into manageable rolls and placed them into large rolling bins for recycling in Sika Sarnafil’s roof “take back” recycling program. Through the program, old membrane is ground into flakes, processed, and put back into the backside of new membrane or used for creating new walkways. Other existing, approved materials such as sheet-metal flashings, termination bars, metal battens and snow diverters also were recycled.

Finally, from this gutter, workers wheeled the debris along the gutter to the southeast end of the building where a man-material hoisting platform was used to lower the bins to the ground. The bins were either emptied into a truck or lifted onto a front-end loader and driven across the street to a staging area that housed the disposal and recycling bins.


Because the original Sarnafil membrane maintained excellent condition, a Sarnafil-engineered mechanically attached polymeric membrane was chosen for the new Rogers Centre roof.

Using swing stages, workers rolled new 80-mil-thick Sarnafil S327-20 membrane in place. The membrane was fastened with new Sarnabars using No. 15 Sarnafasteners. To accomplish this, one worker would set and hold the bar in place while a second worker secured the bar with new fasteners. A third worker operated the swing-stage controls and descended the stage as the other two workers secured the bar.

Once the Sarnabars were installed, workers ascended on a swing stage to install cover strips over the Sarnabars. They hand-welded the first few feet of cover strip to get it in place and then used a Sarnamatic machine to weld the remaining cover strip. To keep the continuity of the welds consistent, workers had to descend on a swing stage at the same speed as the Sarnamatic machine.

As the project progressed, the on-site teams found creative ways to complete their work.

“One of our foremen found that trying to hold the Sarnamatic welder in place all day on a relatively vertical surface while bracing his body against the front end of the swing stage as it descended was tiring and hard on the arms,” Campbell explains. “To combat the issue, an aluminum-framed track was constructed with rubber wheels attached to the frame to allow for movement. A bungee cord was looped through the hook and connected to the welder, taking the weight off the worker.”

At the base of the roof panels where the roofing material was removed down to the deck, workers placed self-adhering Sarnavap SA vapor retarder and secured 1.8-inch-thick Sarnatherm ® polyisocyanurate insulation using 8 fasteners per sheet followed by new membrane.

For the detailing along the ends of the panels, team members installed new 16-gauge galvanized steel liners, brackets and girts to support new 2-inch-thick Sarnatherm polyisocyanurate insulation. Workers tied-in the field membrane to the Sarnaclad drip flashing by welding Sarnafil G410 cover strips.

Other challenges

One of the toughest obstacles to overcome on the project was the weather.

“With constant heavy snowfalls, it made it almost impossible to walk and install the roof system,” Noddle says. “Because the roof is a dome, the snow did not stay on the roof as it would on a typical low-slope roof. The snow from the entire roof area would fall into the 12-foot-deep gutters, which were our working areas, filling them and making access to the swing stages and work area impossible. In some cases, the swing stages would be ripped off the roof into the gutter by the tons of falling snow, damaging them beyond repair.

“To provide better traction on the highly sloped membrane surface, we were able to get D-Gel® Tractor Outdoor Broomball Shoes (shoes with a special grip sole), which are used to walk on ice and prevent slippage. They provided improved grip on the sloped membrane.”

In addition to extreme weather challenges, once baseball season began in April, workers had to work around the Toronto Blue Jays schedule. On home-game days, work hours were shortened.

“If a game started at 7 p.m., we had to be off the roof by 3 p.m. If a game started at 3 p.m., we had to be off by noon, and if it was a 1 p.m. start, there was no work allowed,” Campbell explains. “Once these restrictions were in place, it really altered how much work we could get done. Extra planning was required, and most material deliveries had to be scheduled for when the team was out of town. Craning permits and street closures only could be used when there were no ball games.”

And on days when the weather was good and the Blue Jays wanted to open the roof, all materials needed to be brought to the base of the panels and secured in place so the panels could pass by each other while opening and closing. All safety lines needed to be disconnected, as well.

A home run

The Dean-Chandler Roofing and Flynn Group of Companies teams completed work in February 2020. Although on-site work began later than anticipated because the custom swing stages were not ready, the project was completed faster than the 19 months it took to install the original roof system.

“This was a seven-day workweek operation for a majority of our workers who gave it their all and sacrificed a ton of personal time in doing so,” Campbell says. “This was a full team effort. From the installers to the management team to the consultant to Sika Sarnafil and their staff, this was a huge undertaking and the sequencing and logistics had lots of moving parts—and the parts had to be meticulously sequenced. This was a once-in-a-career project, so to have Dean-Chandler Roofing’s name attached to it is an honor and privilege and makes us extremely proud!”

“I agree with Jay that this was a once-in-a-career opportunity,” Noddle says. “The Rogers Centre is an iconic building and a staple in the Toronto city skyline that is seen all over the world. There were a lot of obstacles, unforeseen challenges, details and high-risk safety precautions that needed to be overcome and addressed immediately with pinpoint precision at the highest quality while not sacrificing safety and production. The most rewarding part is looking back on everything that was accomplished throughout the project and having such a great finished product that can be looked upon across the globe.”

Chrystine Elle Hanus is Professional Roofing’s associate editor and an NRCA director of communications.

PROJECT NAME: Rogers Centre


PROJECT DURATION: November 2018February 2020


ROOFING CONTRACTORS: DeanChandler Roofing Ltd., Scarborough, Ontario, and Flynn Group of Companies, Mississauga, Ontario

ROOFING MANUFACTURER: Sika Sarnafil,® Canton, Mass.

Rogers Centre key marquee dates

Official groundbreaking: Oct. 3, 1986

Opening ceremony: June 3, 1989

First baseball game: June 5, 1989

First concert: Rod Stewart— June 8, 1989

First preseason football game: June 29, 1989

First regular season football game: July 12, 1989

Rogers Centre interesting facts

  • The Rogers Centre complex spans 12.7 acres.
  • The diameter of the building is 700 feet, but the volume inside the stadium with the roof closed is 56.5 million cubic feet.
  • On average, it takes about 40 hours to convert the fi eld from baseball to football mode.
  • Seating capacity is about 54,000; when in baseball mode, seating capacity is 49,000.
  • There are 151 suites located on the 300 and 400 levels of the venue.
  • The Toronto Blue Jays 1993 World Series Title was won on home turf at Rogers Centre (then Skydome) Saturday, Oct. 23.
  • On March 17, 2002, Rogers Centre set a venue attendance record when it hosted 68,237 fans for WrestleMania X8.
  • The names of workers who helped build Rogers Centre can be found in a permanent tribute located in the north end of the 100L concourse.



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