OSSTF Headquarters and Multi-tenant Commercial Building

The Ontario Secondary School Teachers’ Federation (OSSTF/FEESO) is set to break ground for their new Headquarters and Multi-tenant Commercial Building. This progressive 3-storey 124,000 SF Mass Timber project will seamlessly integrate commercial opportunities with the revitalization of the OSSTF/FEESO’s existing office complex in Toronto. Located at 60 Mobile Drive overlooking the Don Valley ravine, the building is a highly sustainable, financially viable, and innovative new workplace that uses Net-Zero Carbon strategies, and targets LEED Platinum certification and high-energy performance levels at 67 kWhr/m2/year. The new OSSTF/FEESO Headquarters and Multi-tenant Commercial Building is spatially divided to house the OSSTF/FEESO offices as well as two floors of leasable tenant space. Upon entering the building, visitors and occupants will immediately be drawn to a light filled, triple height atrium that joins the two spaces; a central feature stair is framed by Glulam (Glued-laminated timber) columns and a vertical wooden screen, dramatically rising to meet a skylight formed by a diagrid of Glulam beams. This diagrid extends from the interior to the exterior to form a continuous canopy over the third-floor terrace shared by OSSTF/FEESO staff and tenants. The building will offer abundant outside views, light, openness, and numerous opportunities for spontaneous interactions between its users. Other shareable spaces on the Main Floor include the Lobby, Café, and Main Floor Terrace, and features a multipurpose, convertible Event Space; this space will be shared not only by the building occupants, but also by outside groups, providing opportunities for engagement with the wider community. The architecture is inspired by WELL and Passive House Design standards and promotes health and wellness at every level: generous 9 x 9 metre structural bays provide optimal sizes for offices and corridors, maximizing the amount natural daylight to reach the interiors; a ‘Fresh Air Strategy’ ensures air moves through the building at a regular rate using building automation systems; large overhangs reduce solar heat gain and control glare; geothermal heating, a rainwater harvesting system for toilet flushing and irrigation, green roof, rooftop solar PV panels, and automated daylight dimming controls further contribute to significant energy savings. The Don Valley ravine edge on which the building sits will also undergo intensive restoration and stabilization through naturalization and water balance strategies. Low Impact Development (LID) measures will control the major overland storm water flow route through the site and into the ravine. The building’s structural components of Cross Laminated Timber (CLT) floor slabs and Glued-laminated Timber (Glulam) beams and columns will be sourced nationally where possible, demonstrating a robust, honest, yet innovative application of natural materials. This highly efficient facility will ensure the OSSTF/FEESO functions as a hub that continues to support public education in Ontario, provide healthy workplace environments for its staff, tenants and visitors, and responsibly meet the organization’s goals of return on investment. Designed to the highest environmental standards, the OSSTF/FEESO’s new headquarters is built on a foundation of social, environmental and financial sustainability.