Project: Durham Consolidated Courthouse in Oshawa, Ontario
Glazing Contractor: Verval Ltée, Gatineau, Quebec
Prominently clad with a mix of spandrel and clear glass the Durham Consolidated Courthouse in Oshawa, Ontario, offers the open transparency designers were looking for.
Verval Ltée, a glass contractor based in Gatineau, Quebec, glazed the six-storey courthouse that has achieved a Silver certification rating from the Canada Green Building Council's Leadership in Energy and Environmental Design (LEED). The building has 2,800 IG units with 1,700 units in the stick system for the large openings framed by Kawneer's 2500 PG Wall and 1600 Wall Systems for the unitized curtainwall structures. The building’s central tower is wrapped with the curtainwall for the first three floors using the pre-glazed stick system with different variants. The north and south sides both have aluminum and glass ‘bump-outs' that protrude from the face of the curtainwall, 30 feet wide and covering three floors.
The sand-based precast concrete with the metal panel accents work with the curtainwall and clear glass vision area to create a sense of transparency and openness.
Viracon supplied 83,000 square feet of Low-E glass for the project that has a 70 percent light transmittance, a key requirement for allowing daylight into the building to save energy by minimizing indoor lighting.
Due to the Low-E glass and other insulating elements of the exterior, the building is 42 percent more energy efficient than the code standard.
Charles Turpin, president of Verval Ltée, says glaziers on site were working on a tight schedule with about four months to close the building envelope.
“We took our top glazier mechanics to direct the project with other local glaziers on site,” says Turpin, adding that much of the unitized curtainwall system was pre-fabricated with a stockpile of panels prepared in advance. “About 75 percent of it was completed in our shop so all we had to do was take it to the jobsite and put it up. It wasn’t a just-in-time schedule. We had to be ready for just about any delay, such as weather, that we had no control over,” he says. “It came together very fast.”
The Durham Consolidated Courthouse was built under the Government of Ontario Infrastructure Ontario Alternate Financing Program (AFP). It is the first courthouse in Ontario to be delivered as a full DBFM (Design, Build, Finance and Maintain) project by Infrastructure Ontario.
The architect for the project was WZMH Architects, Toronto, Ontario, and the general contractor was PCL Constructors Canada. Embury (Kastner Metal) was the aluminum panel supplier.
Verval Ltée is a member of the Architectural Glass and Metal Contractors Association (AGMCA), which is a member of the Canadian Glass Association (CGA).
Low-E: ¼inch (6mm) VE1-2M No.2; ½inch (13.2mm) airspace; 5/16inch (8mm) Clear.
Transmittance: Visible light 69 percent; Solar Energy 32 percent; UV 10 percent.
U-Value: NFRC Winter: 0.29 Btu/(hr x sqft x degrees F); NFRC Summer: 0.26 Btu/(hr x sqft x degrees F).
Shading Coefficient: 0.43
Solar Factor (SHGC): 0.38
Relative Heat Gain: 90 BTU/hr x sqft
Low-E Spandrel: ¼inch (6mm) VE1-2M No.2; 9/16inch (14mm) airspace; ¼inch (6mm) Clear - with VC1350 ceramic frit spandrel No.4
U-Value: NFRC Winter: 0.30 Btu/(hr x sqft x degrees F); NFRC Summer: 0.25 Btu/(hr x sqft x degrees F).
GL-3: Silkscreen: ¼inch (6mm) Ultrawhite - with V1086 sim. Sandblast Silkscreen No.3058 –full coverage No.2; ½inch (13.2mm) airspace; 5/16inch (8mm) Clear.
Transmittance: Visible light 50 percent; Solar Energy 44 percent; UV 22 percent.
Reflectance: Visible light (ext.) 19 percent; Visible light (int.) 18 percent; Solar Energy 15 percent.
U-Value: NFRC Winter 0.47 Btu/(hr x sqft x degrees F); NFRC Summer: 0.49 Btu/(hr x sqft x degrees F).
Shading coefficient: 0.65
Solar Factor (SHGC): 0.56
Relative Heat Gain: 137 BTU/hr x sqft.
Make-up: ¼inch (6mm) Ultrawhite - with V-175 white ceramic frit spandrel No.2; ½inch (13.2mm) airspace; 5/16inch (8mm) Clear.
U-Value: NFRC Winter: 0.47 Btu/(hr x sqft x degrees F); NFRC Summer: 0.49 Btu/(hr x sqft x degrees F).