An ambitious new project to retrofit concrete apartment towers across Toronto is expected to reduce the city's greenhouse gas emissions by as much as five per cent, while rejuvenating neighbourhoods, says Mayor David Miller.

The Mayor's Tower Renewal initiative will provide tools for private-sector owners of the more than 1,000 notoriously energy-wasting high rises in Toronto to retrofit their buildings - with potential to reduce energy use and operating costs by 50 per cent or more.

"Climate change is the issue of our time, maybe of all time," Mayor David Miller said yesterday morning as he unveiled the plan at Humberview Park, near Finch and Kipling avenues in Rexdale, adjacent to 2667 and 2677 Kipling Ave., one of the plan's four pilot projects.

"We have an obligation and a responsibility to lead by example; to do the right thing for the environment, the right thing for neighbourhoods and the right thing for people."

Meanwhile, the city will help with zoning changes to spur the creation of parks, neighbourhood gardens, community and cultural space and small-scale, onsite retail and markets.

Miller called Toronto "a real leader" in the area, and said he has sent the project's Opportunities Book to mayors of the C40, a global climate leadership group of cities, which he chairs.

Buildings participating in the pilot project include: the two buildings at Kipling and Finch avenues; a 192-unit building at Markham Road and Eglinton Avenue West; two buildings of more than 1,000 units in the Jarvis Street-Wellesley Avenue area and a 139-unit building in the Don Mills Road-Sheppard Avenue area.

After the launch, the plan made its way to the city's Executive Committee, where councillors finally supported it unanimously. But not without some objections.

Ward 34 (Don Valley East) Councillor Denzil Minnan-Wong worried that the initiative would act as a "Trojan horse" for unwanted intensification in stable residential neighbourhoods, like Don Mills in his ward.

"In my neighbourhood, we have a lot of apartment buildings that are classified as towers in the park," said Minnan-Wong. "We have been fighting increased intensification at 7 Brookbanks, 44 Valley Wood Rd., and a new development at 20 Graydon Hall. I can tell you if you ask the communities in those neighbourhoods, 'do you want more infill on these developments?' they will say 'no.'"

Other councillors were more enthusiastic about the project.

Ward 7 (York West) Councillor Giorgio Mammoliti said communities in the inner suburbs of North York, Scarborough and Etobicoke would likely welcome more intensification around the base of highrises.

"We don't live in the '50s anymore," he said. "These people they're talking about - they don't exist anymore in the suburbs. The people that are moving into these buildings, many of them don't have cars. In the '50s they did - they moved from plaza to plaza but that doesn't exist in these areas anymore."

That Toronto's high-density, high-rises are integrated in both urban and suburban neighbourhoods is unique in North America, said Miller.

But they're energy hogs.

Current data indicates concrete apartment buildings are 20 per cent less efficient than the average single-family bungalow in Toronto, E.R.A. Architects and the University of Toronto report in their 109-page Opportunities Book.

Built in the late '50s through the '70s, the towers' exposed slab edges, minimal insulation, single-glazed windows and aging mechanical systems act like a "leaky (energy) sieve," says the report.

"It has been a process of managed decline over the last 40 years," Graeme Stewart of E.R.A. Architects said.

Retrofits could range from replacing windows and enclosing balconies to the introduction of renewal energies like geo-thermal, solar, wind and green roofs.

Miller's vision grew from E.R.A. Architects, who presented him with academic research last year completed in partnership with the University of Toronto that indicated it was possible to reduce high levels of greenhouse gas emissions by cladding the exterior of concrete high-rises like those in Toronto.

E.R.A. Architects's Michael McClelland and Stewart later concluded "actions to improve energy efficiency at high-rise buildings could become a powerful driver of community revitalization," states the mayor's report this month on the issue to council's executive committee.

Roslyn Brown, who represents the owners of 2677 Kipling Ave., said the project could improve energy use, the environment, as well as the community.

"It will bring down (operating) costs and reduce energy use," Brown said in an interview. "It's important because we're all looking forward. To continue to have a better life we need to address these things today, not tomorrow."

Stewart estimated individual building retrofits could range from $1 million to $3 million, with "payback" within five to eight years.

In Rexdale, plans include the city leasing the now-vacant, former Father Henry Carr Catholic Secondary School in which to run youth and community programs. The school will become the Rexdale Community Health Centre satellite, said Ward 1 (Etobicoke North) Councillor Suzan Hall.

"It's fantastic. It's long overdue," said Tracy Cato, who lived for seven years in the late 1980s in one of the Rexdale buildings involved in the pilot. "There was always a lot of garbage in the community areas in the building like the lobby, the hallways, the parking lots. An initiative that focuses on maintenance and the environment is fantastic."