Ontario’s First Mass-Timber, Net-Zero Institutional Building Tops Out

Ontario’s first mass-timber, net-zero institutional building tops out.

Photo credit: Salina Kassam

Limberlost Place, the first institutional building in Ontario constructed from mass timber with net-zero carbon emissions, has achieved a significant construction milestone by reaching its highest point in construction.

The installation of the last wood and steel beams has been completed in the 10-story facility situated within George Brown College’s (GBC) Waterfront campus, located in the East Bayfront community of Toronto.

In celebration of a significant construction milestone commonly referred to as “topping off” within the industry, Limberlost Place saw project partners and the skilled trades workforce come together to commemorate the occasion. They signed a beam before it was hoisted into position atop the building.

The construction of Limberlost Place’s structure involved a complex installation process that included a carefully choreographed sequence for placing each mass timber column and cross-laminated slab band. Among the notable features of this structure are three three-story mass timber columns, some of the largest of their kind in North America.

The “topping off” ceremony marks a pivotal moment in the project, signifying a shift in focus towards the completion of the building’s exterior envelope, the initiation of interior fit-up work (which includes the installation of other mass timber elements like the learning landscape feature stairs), and the commencement of the building’s commissioning phase.

Limberlost Place, designed by Acton Ostry Architects and Moriyama Teshima Architects, with construction management overseen by PCL Construction, will serve as the future home to GBC’s schools of architectural studies and computer technology, as well as the Brookfield Sustainability Institute. This innovative and forward-looking facility will provide students with a unique learning environment. Notably, its design and construction have garnered international awards and exceed the Toronto Green Standard’s requirements for reduced carbon emissions, leading to changes in national and provincial building codes for mass-timber structures exceeding six stories.

Limberlost Place’s construction is characterized by its unique blend of mass-timber components sourced from Canada and a structural steel core. This combination forms the foundation of the building’s structural integrity.

A total of 139 cross-laminated timber and concrete composite slab bands underwent prefabrication at an off-site facility before being transported to the construction site for their final installation. This strategic prefabrication approach streamlined the construction process.

Each individual cross-laminated timber piece, boasting a weight of 17,000 pounds, received meticulous preparation, including the incorporation of kerf plates, screws, rebar, concrete, M&E sleeves, roof anchors, and column bases. This attention to detail ensured the structural soundness of the components.

To facilitate efficient installation, the slab bands were methodically organized in the sequence of their installation, precisely designating the location for each timber element within the building’s framework.

The overall structure integrates approximately 1,190 pieces of cross-laminated timber and 571 glue-laminated mass timber pieces, showcasing the extensive use of timber in the construction.

The cross-laminated timber utilized in the project amounts to a substantial 3,310 cubic meters, while the glue-laminated timber totals 822 cubic meters, underscoring the considerable use of timber as a sustainable building material.

Additionally, the construction relied on a significant volume of 5,850 cubic meters of concrete to meet structural requirements.

Further highlighting the complexity and magnitude of this remarkable project, Limberlost Place incorporates over 22,306 distinct steel components, illustrating the intricate engineering and scale of the endeavor.

Project team:

Owner: George Brown College

Architect: Moriyama Teshima Architects in joint venture with Acton Ostry Architects

Construction Manager: PCL Constructors Canada Inc.

Mass Timber: Nordic Structures

Structural Engineer: Fast + Epp

Mechanical and Electrical Engineer: Introba

Structural Steel Design-Assist: Walters Group

Building Envelope: Morrison Hershfield

Sustainability Consultant: Transsolar