BUILDINGS: One Wall Centre mechanical and electrical systems

In order to provide electrical service to the upper floors of the 48-storey hotel-condominium, Arnold Nemetz & Associates took advantage of the interstitial space between the hotel (floors 1-30) and the condominium (floors 31-48) to install a sub-electrical distribution and telecommunications room. The main electrical room on parking level P1 sends 600 volts up a vertical riser space. A step-down transformation to 120/208 volts within the sub-electrical room provides service to the condominium meter centre and common area.

The lighting controls can orchestrate different scenes and dimming in various spaces, and the building has energy-efficient fixtures and a fibre-optic spire light at the top of the building. The security system is interconnected to the existing Wall Centre Tower, and the complex has a fibre optic backbone for high speed internet access.

The mechanical systems designers, Keen Engineering, took into account One Wall Centre’s unusual shape and orientation, which created two solar zones and allowed heat transfer from the south exposure to the north during the shoulder seasons. The mechanical system consists of high-efficiency water source heat pumps. In order to avoid high static pressures at the bottom of the building a plate heat exchanger was used. The plate heat exchanger allows a “close temperature” approach that ensures efficient performance of the heat pumps.

The potential problem of stack effect (where outside air is sucked into the lower floors and rises) is minimized by using a central vertical exhaust system with horizontal discharge in the structural transfer floors and at the top of the building, rather than having individual exhaust outlets from every unit. The ground floor has higher rates of outside air intake to prevent cold air entering.

Multi-stage centrifugal booster pumps provide sufficient pressure to operate the plumbing fixtures at the top of the building, while a series of pressure-reducing stations minimize noise and water consumption.

Client: One Wall Centre, Peter Wall Chair & CEO

Structural engineer: Glotman Simpson (Robert Simpson, P.Eng. Micheal O’Keefe, P. Eng.)

Electrical consultant: Arnold Nemetz & Associates (Steve Nemetz, P.Eng.)

Mechanical consultant: Keen Engineering (Willie Perez, P.Eng.)

Architect: Busby & Associates (Peter Busby)

Geotechnical engineer: Geopacific

By Virginia Heffernan

Glotmen Simpson