Ontario Secondary School Teachers Federation (OSSTF) New Headquarters and Multi-Tenant Commercial Building

The Ontario Secondary School Teachers Federation Headquarters (OSSTF) is a three-storey, 124,000-square-foot mass timber building overlooking the Don Valley Ravine in Toronto. It is highly sustainable, using Net-Zero Carbon strategies, targeting LEED Platinum certification and high energy level performance (67 kWhr/m²/year). The building was crafted with cross-laminated timber floor slabs and glue-laminated timber beams and columns, featuring a plethora of windows which beautifully compliment the timber and allow for as much natural light as possible.

Owner: Ontario Secondary School Teachers Foundation

Mass Timber Supplier: Nordic Structures

Structural Engineer: Fast+Epp

Architect: Moriyama Teshima Architects

Porject Awards: 2023 LOOP Design Awards for Concept Design Category, 2024 Architecture Press Release Global Future Design Award – Gold Winner, 2025 Canadian Wood Council Ontario WoodWorks Award for Excellence in Wood Design, 2025 Architizer A+ Award for Commercial – Office – Low Rise (1-4 Floors) for Popular Choice