The Ontario Secondary School Teachers’ Federation (OSSTF) Headquarters and Multi-Tenant Commercial Building is a progressive 3-storey, 124,000 SF mass timber project that uses net-zero strategies, and seamlessly integrates commercial opportunities with the relocation and revitalization of the OSSTF’s office centre in Toronto. The building houses the headquarters of the OSSTF and represents all the educators, educational assistants, psychologists, secretaries, speech-language pathologists, social workers, plant support personnel, attendance counselors and many other education professionals in the secondary school system in Ontario, as well as additional tenants. All design decisions were rigorously assessed for long-term value, health and wellness of employees, and operational savings.
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The Ontario Secondary School Teachers’ Federation (OSSTF) Headquarters and Multi-Tenant Commercial Building
Office Building (Built)
Firm
Moriyama Teshima Architects
Architect/Designer
Carol Phillips
Design Team
Phil Silverstein, Cathy McMahon, Deya Iskandarova, Corey Brown, Emmanuel Awuah, Maya Desai, Sean Robbins, Kayley Mullings, Gord Doherty, Paul Aquilina
Location
Toronto, Ontario, Canada
Country
Canada
Photographer/Copyright
©Moriyama Teshima Architects
Website
www.mtarch.com
Instagram
@moriyamateshima
Facebook
https://www.facebook.com/moriyamateshima/
YouTube
https://www.youtube.com/user/moriyamateshima
Overlooking the Don Valley ravine landscape, the building is a highly sustainable, financially viable, and innovative new workplace that is on target for LEED Platinum certification and high-energy performance levels at 67 kWhr/m2/year. Designed to the highest environmental standards, the facility is built on a foundation of social, environmental, and financial sustainability.
Despite perceived premiums for a mass timber structure, after thorough analysis, the OSSTF went forward with a mass timber LEED Platinum solution that also invested in naturalized restoration of the ravine edge. Constructed out of cross laminated timber (CLT) floor slabs and glue laminated timber (GLT) beams and columns, structural components have been sourced nationally where possible, and demonstrate a robust, honest, yet innovative application of natural materials.
The mass timber structure of the building uses a 9m x 9m grid of glulam columns, beams, and purlins with a cross laminated timber (CLT) infill panel for the general floor system. This is an optimal grid for office layouts and was chosen for its optimization of the timber volume. Flexibility for tenants and future changes is facilitated using a raised floor system that also assists with acoustics and wire control and is a fully integrated underfloor air distribution (UFAD) system delivery.
This highly efficient facility ensures that the OSSTF functions as a hub that continually supports public education in the province, provides healthy workplace environments for its staff and visitors, and responsibly meets the organization’s goals of financial resiliency.
The new Multi-Tenant Commercial Building is spatially divided to house the OSSTF Headquarters as well as two floors of leasable tenant space. Joined by a central atrium, the building offers abundant outside views, light, openness, and numerous opportunities for spontaneous interactions between the OSSTF staff and tenants. Furthermore, shareable spaces on the ground floor include the lobby, café, and ground floor terrace, and features a multipurpose, convertible Event Space; this space is shared not only by the building occupants, but 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 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 LEED Platinum design achieves significant reductions in energy consumption and a reduction of greenhouse gas emissions. The building systems are comprised of geothermal heat exchange, passive natural ventilation system used together with a decoupled active mechanical system, and energy generation from the rooftop photo voltaic array. The key player in the building performance is the façade that contributes most significantly to the environment and experience for the building occupants.