When Toronto’s Yorkdale Mall graces the cover of a magazine, it’s the photos of the revised glass entrance way that are front and centre.
The $220M East Expansion to the Yorkdale Shopping Centre added an additional 145,000 sq. ft. and 40 new stores. The focal point of this expansion was the new entrance that welcomes public from the highway and Yorkdale subway station. The scope of the project involved the construction of two side-by-side feature glass walls as part of the Yorkdale Shopping Centre East Expansion.
Termed the “Sail Wall” and “Cable Wall”, over 5500 square feet of frameless structural glazing was designed and installed using two very distinctive methods, with the majority of the glass panels being supported by a no-holes-in-glass concept. Here’s a breakdown of what went into each of these unique glass wall systems.
Focus on the facetted Sail Wall.
The Sail Wall
This wall was aptly named as this façade combined facetted and trapezoidal glass panels to form the shape of a ship’s sail. Spanning over 27m [90’] in width and 22m [66’] high at its apex, this 4,200 sq.ft. glass wall required a number of custom solutions to ensure it would hold.
To support this heavy load, we cast our custom spiders from high strength duplex stainless steel. 11 different types of Stella spiders were used on the Sail Wall to accommodate cantilevered glass panels plus varying glass thicknesses and make-ups. Using computer FEA analysis and actual product testing, we determined where the highest loading points were, and used spiders made from duplex at these critical junctures.
To create the look of curved glass, while maintaining cost efficiency, each glass bay was facetted at approximately 6°. Unique silicone foam gaskets were created to alleviate stresses in glass and provide a weathertight seal at the joints.
A Design Twist: Stella designed a system so glass wall could support angled skylight at the apex.
To maintain a thermally-insulated enclosure, our thermally-broken PC3710 perimeter channel was used around the sill and skylight jambs, and at the south side of wall, we created a custom expansion joint detail to interface the existing structure with this new wall.
This helped to ensure that Yorkdale would receive a LEED Gold certification – the first enclosed retail shopping centre over 1M sq.ft. to do so.
The Cable Wall
The second entrance wall to Yorkdale Mall, was not as geometrically challenging, but the cloverleaf-shaped ledge-support fittings required an involved design and construction sequence. Spanning 8.2m [27’] wide and 10m [33’] high, this wall is comprised of 20 square glass panels supported by pre-tensioned stainless steel cables and vertical rods to depict a floating wall.
We assisted with the design for this project so that we could support the designers’ vision and consider all of the fluctuating ambient temperatures, cable relaxation, connection to steel columns, and dynamic movements of the wall system during service.
In the end , “invisible” design details is what makes the glass stand out. From thermally broken perimeter channels to heat treated stainless steel tension rods, all of these small pieces work together to support the weight of the glass as well as accommodate differential movements within the building structure.
Stella Services Provided
- Project Coordination with Glazing Contractor, Architect, and Structural Engineer
- Shop Drawings and Drafting
- Engineering Design and Analysis
- Component Testing
- Coordination with Survey Subcontractor
- Analysis of As-built Survey Data
- Calculation of shim counts based on site as-built column scan
- Hardware and Cable Tensioning Hardware Supply
- Site Supervision of Initial Cable Tensioning
- Warranty and Maintenance Documentation
Project Team
- Developer: Oxford Properties Management
- Architect: MMC Architects
- Structural Engineer: RJC Engineers
- Glazing Contractor: TAGG
Awards
- 2017 ICSC Maple Leaf Gold Award for Design and Development Excellence
- 2017 International Property Award for Best Retail Architecture Design – Canada / North America
