Building Envelope Feasibility Study – Wilson Subway Station, Toronto Transit Commission, Toronto ON
Philip Brearton, Building Envelope Specialist
Viluong Huynh, Architect
R.J. Burnside – Traffic Consultant
Altus Group – Cost Consultant
Senior Project Engineer Toronto Transit Commission
In collaboration with NORR, Cion was retained to provide a feasibility study (preliminary design review) that described the constraints of the construction project and provided three different design solutions. NORR provided senior review of the associated structural, electrical and mechanical systems. One major challenge was the logistics of replacing 300 concrete panels from a subway station that is operational 21.5 hours per day and is situated within one meter from the north and southbound Allen Expressway.
This subway station was originally constructed in the 1970’s at very close proximity to the Allen Expressway thereby leading to accelerated environmental deterioration of the precast concrete wall panels and various metal building components. Cion was retained to assess the precast concrete wall cladding and associated building elements at the Wilson Subway Station and to provide a building envelope renewal strategy.
Cion conducted a site investigation and found advanced corrosion of steel structural components in addition to heavily deteriorated precast concrete panels. Cion arranged site meetings with demolition contractors as well as precast concrete panel manufacturers to discuss panel design, demolition and logistic options. Three design options were submitted to TTC, each of which included transportation designs and each option costed by an outside Cost Consultant. The new precast concrete panel solution was chosen by TTC and the project is currently proceeding through design development.