Toronto Mulls Mandatory Green Roofs

By John Lorinc
Green roofAndrew Councill for The New York Times The city of Toronto is considering making green rooftops, like the one above in Washington, mandatory for most new buildings.

After a high-level debate about the virtues of green roofs, the Toronto city council has found itself confronting a gritty political dilemma. What works better – the carrot of financial incentives or the stick of regulation?

Typically, local or state governments opt for the former, providing grants and tax abatements to building owners who install green roofs, which proponents say improve insulation and roof life, absorb greenhouse gases and mitigate the urban heat island effect. Chicago officials often tout the fact that the city leads all other North American cities with more than 1 million square feet of installed green roofs in more than 250 locations.

But the Toronto council this month got a look at a proposed green roof by-law that would make such installations mandatory on certain new developments with a gross floor area exceeding 54,000 square feet. The measure, which is a component of Mayor David Miller’s environmental strategy, proposes greening 30 to 60 percent of the roof area, depending on building size. Exemptions include schools, industrial structures, low- to mid-rise apartment buildings and affordable housing.

If adopted, the city of Toronto would be the first municipality in North America with a mandatory green roof by-law. Similar requirements exist in Japan, Switzerland, Germany and France, according to Steven Peck, president and founder of Green Roofs for Healthy Cities, an industry association based in Toronto. Mr. Peck said he expects the measure to pass. “We have a very broad base of support for this,” he said.

That may be an overstatement. The council was to vote on the by-law this week, but the decision has been postponed for a month so the city can consult with developers, who have loudly opposed the measure, arguing that it would scare away investment due to the high cost of green roofs. Saying green roof installation should be voluntary, building industry representatives told The Globe and Mail that such add-ons could increase construction costs by $18 to $28 a square foot.

Mr. Peck, who estimates the figures range from $10 to $40, dismisses the developer concerns about investment flight. “I don’t think it’s plausible. If you’re a developer of new buildings and you’re not embracing the rising tide of green building opportunities, you’ll be left behind.”

As it happens, subsidies and by-laws aren’t the only policy tools available for green roof promotion. According to the International Green Roof Association, German municipalities also rely on new storm water taxes, which are levied separately from sewer taxes. This distinction provides owners with an incentive to take steps to contain storm water on site, including installing green roofs. The I.G.R.A. says homeowners with such improvements can recoup 50 to 100 percent of the levy.

Comments are no longer being accepted.

Jack April 16, 2009 · 1:22 pm

Nice, an article about Toronto accompanied with a picture of Washington, D.C. (Washington Monument and the Old Post Office Building are clearly visible).

Mark April 16, 2009 · 6:33 pm

Hey Jack,
Get over it, Toronto is a usual stand in for “New York”.

Mitch Sprague April 16, 2009 · 6:37 pm

If I could convince my condo association we’d be doing this to our building.

Anonymous April 17, 2009 · 1:03 am

“German municipalities also rely on new storm water taxes, which are levied separately from sewer taxes. This distinction provides owners with an incentive to take steps to contain storm water on site, including installing green roofs.”

How on earth would they know how much water entered the storm sewer from any given property? They tried to tell us when they started charging a storm sewer fee, that it would go by how much concrete was on it. That’s not how it ended up. All businesses ended up with having to pay only $25/mo, even those with the largest parking lots.
(I maintained that storm sewers are part of the street system – and they have been using the fees for other projects – a misappropriation of funds to say the least.)

While green roofs may be a good idea, they should not be mandated. What’s next, a law to make sure you keep your gree roof mowed? Please, give me a break.

Jorg Breuning April 17, 2009 · 6:20 am

It is funny to see how things in North America are going from one extreme to another – always and no matter what it is.
Not even 10 years ago roofs in North America had only the function to protect the inside of buildings against the elements and to generate a descend profit to roofers because there was a constant need for fixing and repair.
Now with the green wave from Europe everybody’s attention is on the roof and has ideas how wonderful it would be if we created a paradise up there. Since we successfully destroyed the paradise on the ground dreamers believe roofs – especially green roof – can bring things back, right into the city and with a huge job and profit machine.
I would like to suggest three things:
1st: Stop dreaming, start thinking.
2nd: Fix the problems on the ground. This is cheaper, more efficient and less risk for the investment of a building.
3rd: Standardize green roof technology first as it is in other countries since decades and the Cities should be a role model with countless green roof installations first. Make a law based on this experience.
That’s how it is in Germany – good luck –
Jorg

David April 18, 2009 · 10:54 am

The mayor of Toronto has a way of shooting before he aims. High-ride residential buildings in Ontario are required to be covered by a new home warranty from the sole provincial provider.

As of yet, there is not recognized technical standard governing the construction of green roofs in Ontario, which may make getting warranty coverage a bit problematic.

If the mayor has any sense, he’d be calling for development of such a standard before mandating such a measure.

The claims by green roof advocates are dubious at best. If you want to improve the insulating value of a roof, installing extra insulation is more effective and cheaper. If you want to reduce the heat-island effect, paint it white.

This whole move to embrace green roofs is just anther chapter is the silly side of the green movement.

Jörg Breuning April 18, 2009 · 1:39 pm

As more “green” you request by law the more costs will be generated while the environmental benefits will dramatically decrease.
At the end a new industry will be dead before started, no help for the environment and a bigger hole in the pocket of the people than before. This is a lesson learned from Europe where things obviously even more head than I thought.

Marshall Leslie April 18, 2009 · 6:10 pm

While Toronto’s proposed Green Building Standard should be applauded (and would be a much better subject to write about), its proposed Green Roof bylaw is badly crafted. For several reasons:
1) The City did not critically examine the benefits that advocacy groups have argued and conduct independent research. Canada’s own National Research Council has gathered evidence which indicate that the argued energy savings of green roofs only occur 3 months of the year and are non-existant the rest of the time. It also idicates that water retention benefits don’t exist.
2) The City did not examine several early maintenance problems and premature failures that exist within its own boundaries – including roof failures that it actually features on the web site it created to inform the public about local green roofs!
3) The city created a Technical Advisory Group (TAG) that did not include any roofing contractors, manufacturers or building science consultants; and which actually issued a report with no recommendations on wind uplift, fire resistance and maintenance.
4) the bylaw doesn’t meet the City of Toronto Act – which allows the City to exceed building code requirements – but doesn’t allow the City to skirt them.
5) the bylaw unwittingly exposes Toronto’s Chief Building Official (CBO) to liability for negligence because the City would issue a special permit based upon a plan and proposal that is untried and flawed. The CBO thus awards design approval and must accept responsibility for the results.
In this case, haste has all the potential to bring down the roof.

Fiona April 20, 2009 · 2:42 am

— Anonymous

In new developments, designers usually try and get water into pipes, and water flows fast through pipes, into more pipes and then ultimately into the city storm water or sewerage system. The more and more areas are drained into pipes, the quicker it gets into the systems, rivers etc, which can cause flooding.

A current problem for city engineers is keeping up with a rising amount of water being sent in to the system, so if water can be delayed, held back or prevented from getting into the sewers, even better.

If it rains onto a field it can take a long time for the water to shed onto an adjacent road or paving etc and get into the drainage system, by which time the rain might have stopped… So thats the idea -drainage wise at least. Green roofs, hold some water back and on large scale developments or lots of developements it can make a huge impact.

Have a look at the Ford Truck Assembly Plant at Dearborn. Impressive.

Tony Brown September 23, 2009 · 10:25 pm

I don’t know If I said it already but …I’m so glad I found this site…Keep up the good work I read a lot of blogs on a daily basis and for the most part, people lack substance but, I just wanted to make a quick comment to say GREAT blog. Thanks, :)

A definite great read..Tony Brown