Hamilton student apartments could be first in mid- to highrise category to gain this exceptional rating
Jul 07, 2007 04:30 AM
Special to The Star
When developer Robert Manherz, 46, rebuilt the family cottage in Haliburton several years ago, he went for green construction.
The retreat functions off the grid, running on solar and wind power, supplemented in winter by a generator. He used an insulated concrete form system to build the structure, stacking foam forms and filling them with concrete to produce a well-insulated wall with no air or moisture infiltration.
Now, the Ancaster resident is going for green in an even bigger way. He hopes to secure a top environmental certification – LEED platinum – for a 107-unit nine-storey student rental apartment building called West Village that his company, Dundurn Edge Developments, is putting up near McMaster University in Hamilton.
So far, the highest LEED certification for a mid-rise and highrise residential buildings in Canada is silver. Some other projects targeting LEED platinum are also in the works: a six-hectare redevelopment in Victoria, B.C., and three social housing buildings for Brampton. But it looks like Manherz and West Village might cross the Platinum certification line first if they secure enough credits in the final audit.
Manherz is again using insulated concrete form construction for the building. The $20 million projectis thought to be the largest using ICF in North America.
"In terms of energy savings, heating and cooling perspectives, it’s one of the best ways of doing it," says Manherz, who also heads the company that will manage the apartment building.
He expects the heating and cooling load to be 75 per cent less than for conventional construction because of the superior thermal envelope coupled with other elements such as high performance windows.
The concrete used for the walls contains 40 per cent slag, a byproduct of steel production, that helps Dundurn earn a LEED credit for recycled materials.
Building to a platinum LEED standard is considerably more difficult than aiming for gold, says Manherz. "You need a certain number of points to get to platinum, and, basically, most of the easy points, the relatively inexpensive points, you’ve already used up to get to gold."
Those easy credits include such things as bike storage racks and low off-gassing carpets.
Going through the process represents a learning curve both for Manherz’s company and for his trades and suppliers.
"As you get more experience and work on multiple buildings, you get more efficient at it, and your costs generally won’t be that much more, if not the same as you would normally have for a conventional building," he says.
Manherz estimates the construction premium for West Village at about 7 per cent: "If this was our second or third building to get to Platinum, it might be a 3 per cent or 4 per cent premium."
To garner enough points for platinum, Manherz and his suppliers had to choose products carefully, and they encountered challenges along the supply line.
Case in point: the 1,200 bedroom doors. Standard ones cost $30 to $40 each, but doors made from sustainably harvested wood certified by the Forestry Stewardship Council cost $200 each. Because Manherz was earning enough LEED points on cabinetry and other elements, he opted for standard doors.
When Manherz and his colleagues began looking at the LEED program, they knew they had a good start with the wall construction system. As they went through the checklist, they were verging on the 52 points needed to cross into the platinum range.
"So we thought, if we’re this close, let’s go for platinum. So here we are."
Among the features helping Dundurn Edge Developments toward LEED platinum: solar heating for domestic hot water; captured rainwater used for flushing toilets; low-flush toilets that use 4.6 litres as opposed to 6 litres; low-flow fixtures for showers and sinks; EnergyStar appliances; heat recovery ventilators in each unit; meters for monitoring electricity use in every unit; a kill switch for tenants to easily turn off all lights and fans when they leave their units; wind turbines; a reflective white roof to reduce heat gain; and landscaping with native plants that don’t need water.
Manherz retained Enermodal Engineering Ltd., a consulting firm with LEED expertise. The architect is Rick Lintack, of R.F. Lintack Architect.
Manherz plans to rent the two- to five-bedroom apartments at West Village for $475 per person per month, plus a $50 utility charge.