May 13, 2010

DRYVIT SYSTEMS CANADA

Exterior cladding in EIFS is being used as a means of building renewal that also boosts insulation values.

Toronto’s tower renewal program promotes energy efficiency

PETER KENTER

correspondent

With energy costs projected to increase, existing multi-tenant buildings will come under increased pressure to retrofit to save on energy costs while maintaining a “livable” building.

“If water, air, cold or heat can get in, these conditions will cause real damage and your energy dollars are going out your building’s envelope,” says Brian Shedden, a senior project manager with GRG Building Consultants of Newmarket, Ont. “Buildings that are particularly vulnerable include a huge stock of high-rises built primarily in the 1960s and 1970s affecting thousands of units across Canada. These buildings are essentially middle-aged energy hogs in need of big investment and repair.”

In Toronto, Mayor David Miller’s Tower Renewal program will encourage owners of more than 1,000 residential apartment towers to retrofit their buildings. “A lot of these buildings have no energy efficiency built into them,” says Shedden. “They’re leaking energy 24/7 and in that condition, they may as well have the windows open.”

The consultant is currently conducting a case study of a single east-end tower that represents significant opportunities for energy cost savings.

“We’re turning that academic exercise into reality in a project that will present the first full-fledged tower renewal as part of the mayor’s program,” says Shedden.

“We need to work on ways to show them how to get the best results for their retrofit investments and show how energy savings over the longer run will pay for the improvements now. <0x000A>While some building owners may optimistically tell us they need a five-year payback to go ahead with a retrofit, we can at least present them with a business case that shows them that a longer-payback period is still a good deal.”

The building is undergoing a full audit that will include a review of the building’s history, a building condition survey, an energy use analysis, interviews with residents, and a cost analysis involving money currently spent on energy, maintenance and repairs. Once energy retrofit options have been identified, the building will undergo an actual retrofit and undergo monitoring over the space of several years, in co-operation with the Toronto Atmospheric Fund, to determine the payback period.

“This is a way to take the guidelines of the mayor’s Tower Renewal Program and offer a real example of what an energy retrofit can achieve,” says Shedden. “With rent controls, a lot of owners find it a tough prospect to invest energy retrofit dollars into their buildings because they can’t pass those costs along to the end user. This is the type of proof that people are looking for. We need to get this program established and ready to roll, with owners, contractors, trade unions, manufacturers, suppliers and consultants ready to participate.”

The candidate building — still under wraps until an announcement this month — is typical of buildings erected during the 1970s and 1980s.

“We’re identifying the four major retrofits that will recoup the most money for the investment,” says Shedden.

The consultant is recommending the owner first replace all of the single-pane windows in the building with new, double-glazed high-performance windows, improving window insulation value from an R1 to rating to R4. The second phase of retrofit would involve over-cladding the existing masonry and concrete with Exterior Insulation Finish Systems (EIFS).

“If you over-clad the exterior with three inches of foam using EIFS, you not only take the existing walls from an R8 to an R20, you’re also taking 45-year-old brick in need of repair and rejuvenating that surface,” says Shedden. “EIFS isn’t widely used on residential high-rises to this point, but it has wide acceptance on commercial structures — almost every Tim Hortons in Canada is built with EIFS.”

The third retrofit option is a replacement of the building’s uninsulated roof, which was installed in 1967. The new inverted roofing system features foam insulation above the membrane and increases the insulation value from essentially nothing to R20.

“Finally, we would be replacing the southern exposure of the building with solar wall, a convective heating system that uses the power of the sun to heat the air rising within it,” says Shedden.

Shedden says that such a four-step retrofit would essentially push the “green re-set button” on these buildings, adding considerably to their longevity.

“If you wait 10 years on a 50-year-old building, all you get is a 60-year-old building in worse shape than before,” he says.

“The other advantage to retrofitting early is to get the work done when demand is moderate. If there were a dramatic increase in the cost of energy, it would drive up the cost of the work, commensurate with demand. As it is, there’s enough work available here so that people in our industry could spend the rest of our lives doing nothing but jobs of this kind.

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