New ETFO headquarters a benchmark design

As Originally Seen in the Daily Commercial News :

The Elementary Teachers Federation of Ontario (ETFO) has set a benchmark in sustainable design with its recently completed headquarters.

The 86,000-square-foot building in downtown Toronto is targeted to achieve a LEED Platinum certification for, among other things, a spate of energy-saving features.

The geothermal system, which handles the majority of the heating and cooling demands, is a prime example. General contractor Bird Construction took a novel approach to its installation.

Conventional wisdom dictates a pre-construction start, but Bird held off until the four-storey structure was up.

The later installation of the geothermal system allowed the contractor a three-month head start on constructing the building, explains Sosio Porretta, Bird’s project director.

Bird’s work started on site in June 2011; substantial performance followed 22 months later, he says.

“It was important to meet the construction schedule to meet ETFO’s anticipated move-in schedule,” says Porretta, adding that the decision to install geothermal after construction helped to ensure deadlines were met.

The work involved drilling 84 holes 450 feet deep at the base of the parking garage. It was the first time Vancouver-based Fenix 
Energy Ltd. had ever installed a geothermal system under an existing building, says Porretta.

The system is tied into a space heating/cooling network; consisting of hydronic capillary matts installed in the ceiling grid, says Raymund Ng, Bird’s project manager. The matts are made up of five ml polypropylene pipes carrying that carry water for heating and cooling.

The mechanical/electrical systems are installed in an access floor space of each of the building’s four storeys, adds Ng. A low-volume, low velocity ventilation system disperses fresh air from raised floor plenums.

The building’s structure is primarily poured-in-place concrete, but a portion is constructed in structural steel cantilevered over a lane used for garbage pickup and loading dock deliveries.

On a tight downtown Toronto site, the building had up to 145 workers during peak construction. With only one site access and no place for materials laydown, all deliveries were handled on a just-in-time basis, says Porretta.

“If a guy showed up with a delivery that wasn’t scheduled, he was sent home,” he says.

Among other sustainable design features of the building is a large portion of the roof which is covered in a mat of groundcover that acts as an insulation barrier and as a filter to pretreat rainwater captured in a cistern for reuse in landscape irrigation. A second rainwater cistern is used for toilets and urinals, says Porretta.

The elementary education headquarters features a building envelope with a sophisticated series of automated solar shades. To prevent the shades from damage, sensors that detect high winds enable a mechanism to retract the shades into a protective cover, says the project director.

Inside, occupants will have manually controlled roller shades to operate.

KPMB Architects designed floor-to-ceiling glazing for most regularly occupied spaces to maximize daylight. Operable windows contain an automatic strike to prevent opening during high heat/humidity periods. The curtainwall features slender fiber cement panels, imported from Germany, says Porretta.

The showpiece of the building is the lobby’s four-storey atrium which is capped with a large skylight, complete with a tensioned horizontal shade system. A cantilevered staircase in the atrium features a glass balustrade; on either side of the staircase at each floor is a bridge to offices, he says.

The design team, led by KPMB, had to accommodate a large tree on site by incorporating a u-shaped notch in an exterior wall.

“Everyone had to work around the tree during construction to preserve it,” says Ng.

Another unusual aspect to the building’s design is an extensive series of moveable walls (partitions) on the ground floor. The partitions were designed to retract into a pocket wall — a system that presented a challenge to design in a constructible fashion, says Porretta.

“Like many things on this project, it involved thinking out of the box.”
New Etfo Headquarters A Benchmark Design : News & Media : Bird Construction