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Green Roofs..... Toronto of the future

AlvinofDiaspar

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A good number new medium/large scale projects already have greenroofs anyways - so it's not exactly ground-breaking in any sense of the word.

AoD
 

wyliepoon

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I wonder how the costs of installing and maintaining green roofs would affect future developments in the city if this bylaw is to be put in place. Would developers rather pay the fine than install a green roof, or would they avoid building in Toronto altogether (this being the only city with such a rule). From my understanding, green roofs don't come cheap.

I'd like to see roof gardens (such as a deck or patio containing an assortment of potted plants, perhaps with public access, like at the Robertson Building or 401 Richmond on Spadina) provided as an alternative to green roofs if the developer does not wish to install one.
 

adma

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Oh, darn. Now I gotta buy a few cans of green paint to slather my slate roof with, just like Smiffy of the Bash Street Kids might
 

khristopher

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What good does it to to have some grass and shrubs on a roof anyway? I'd rather the developments be forced to provice greens pace on their property at the base, or donate money to build parks within the city it's developing in.
 

lesouris

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What good does it to to have some grass and shrubs on a roof anyway?
I understand that they help mitigate the urban heat island effect amongst other things.

From Wikipedia:

Green roofs are used to:

*Grow fruits, vegetables, and flowers
*Reduce heating (by adding mass and thermal resistance value) and cooling (by evaporative cooling) loads on a building — especially if it is glassed in so as to act as a terrarium and passive solar heat reservoir
*Increase roof life span
*Reduce stormwater run off — see water-wise gardening
*Filter pollutants and carbon dioxide out of the air — see living wall
*The soil and plants on green roofs help to insulate a building for sound; the soil helps to block lower frequencies and the plants block higher frequencies.
*Filter pollutants and heavy metals out of rainwater
*Increase wildlife habitat in built-up areas
*A green roof is often a key component of an autonomous building.

A 2005 study by Brad Bass of the University of Toronto showed that green roofs can also reduce heat loss and energy consumption in winter conditions.

In a recent study on the impacts of green infrastructure and in particular green roofs in the Greater Manchester area, researchers found that adding green roofs will help keep temperatures down, particularly in urban areas: “adding green roofs to all buildings can have a dramatic effect on maximum surface temperatures, keeping temperatures below the 1961-1990 current form case for all time periods and emissions scenarios. Roof greening makes the biggest difference…where the building proportion is high and the evaporative fraction is low. Thus, the largest difference was made in the town centers.â€
 

Automation Gallery

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afransen

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What good does it to to have some grass and shrubs on a roof anyway? I'd rather the developments be forced to provice greens pace on their property at the base, or donate money to build parks within the city it's developing in.
Advocating towers in the park?
 

valkoholic

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Some thoughts:

Looks like a development charge to me. Developers can build a green roof or pay $100,000. They'll do the math and pick the cheaper option.

Residential buildings of around 7 floors or less, non-profit housing, schools, and insustrial buildings are exempt. So this will mean this by-law will be very painful for medium sized developments who have to pay for the roof (or the fine) but can only spread the cost over 150 or so units. Office buildings and big condos will just pay the fine.

I'm not a lawyer, but is is true that because this is a municiapl code a developer cannot seek relief through a site-specific zoning by-law?

And in terms of the benefits of green roof technology, my understanding from 'green people' is that painting your roof white gives most of the befits of a green roof at a fraction of the cost.
 

BobBob

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Painting the roof while would help with the heat island effect, but not any of the other 8 points listed a few posts earlier.
 

valkoholic

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Painting the roof while would help with the heat island effect, but not any of the other 8 points listed a few posts earlier.
True. I don't really have a problem with the green roof thing, I just get nervous when the City of Toronto comes up with 'this is what's best for buildings' legislation. From what I've seen from other new by-laws the results are clumsy and difficult to manage.

Oh, and I was wrong about the $100,000. It looks like the fine is $200 per square metre of green roof not built. I guess that will be more or less than the $100,000 depending on the size of building.
 

AlvinofDiaspar

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From the Globe:

URBAN OASES

'Green roofs' get watered down
Proposal exempts many buildings from environmental plan, but developers still balk
JEFF GRAY

April 15, 2009

Major developers say a proposed Toronto bylaw mandating environmentally friendly "green roofs" presents a host of problems and should be put off in favour of a voluntary program.

But green-roof advocates also criticized the new draft rules for exempting industrial buildings, non-profit housing, schools, and residential buildings less than 23 metres (about eight storeys) high. It would also exempt buildings with a gross floor area under 5,000 square metres.

The proposed bylaw would mandate specially irrigated rooftop gardens that are said to reduce air-conditioning costs and mitigate the "urban heat island" effect blamed on pavement and dark roofs.

Part of Mayor David Miller's climate-change initiative, the move was deferred for fine tuning yesterday and was to return to a meeting next month of the city's planning and growth committee.

One development industry representative said more talks with city officials are needed and that heeding calls from deputy mayor Joe Pantalone to toughen the bylaw could drive development out of Toronto.

"We need to sit down with city staff to figure out where we're at," said Steve Daniels, a development planner with Deltera Inc. (part of the Tridel Group) and a representative of the Building Industry and Land Development Association.

He said that green roofs could cost hundreds of thousands of dollars - $18 to $28 a square foot - on major condo projects, and warned that the new rules could conflict with existing regulations, such as fire rules in the Ontario Building Code.

But Mr. Daniels said the industry does not oppose the concept of green roofs - an idea that is much more developed in Europe. Advocates claim the roofs could save energy and clean the air.

Steven Peck, president of Green Roofs for Healthy Cities, a 10-year-old Toronto-based industry association, warned that the city's proposed bylaw falls well short of moves in New York and other U.S. cities.

"We're very concerned ... that there's been a watering down of these requirements and this will set a very negative precedent for other jurisdictions across North America," Mr. Peck told the planning and growth committee yesterday.

Under Toronto's proposed rules, buildings with gross floor areas of 5,000 to 9,999 square metres would be required to cover only 30 per cent of their roofs with greenery, with that percentage increasing as the footprint gets larger.

Mr. Pantalone, the deputy mayor, also criticized the draft bylaw, saying city council unanimously approved a climate-change policy two years ago that "called for aggressive action, not for tepid, let's step back and see which way the wind is blowing."

Saying he was "surprised and dismayed" at the draft rules, he argued new public housing, schools and industrial buildings, as well as new low-rise buildings on main streets, should be included.
_____

valkaholic:

And in terms of the benefits of green roof technology, my understanding from 'green people' is that painting your roof white gives most of the befits of a green roof at a fraction of the cost.
That's the so called "cool roofs" - which I think should be an option under the bylaw especially in cases where greenroofs are not practical for structural or other reasons. Not a big fan of the fine itself - which sort of make it conditional. Enforcement should be a relatively simple affair compared to other city initiatives (think coffee cups and street food) - just make it part of site plan approval and have like a one-time verification after built out.

AoD
 
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Chuck

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Though a good idea in principle, I do see a few flaws. For one, it exempts short buildings. This is a problem because the taller the building, the less suitable it is for a green roof! This is due to increased exposure on higher floors, the tendency to have larger mechanical units and cooling towers to service a larger building, and a smaller floor plate for tall buildings. The combined effect is reduced plant selection, and decreased green roof coverage.

Another flaw is the penalty. Many buildings will simply not be suitable for a cool roof, but knowing how slow things move at city hall, it could be months if not years to exempt one's self from the penalty. On the flip side, the penalty is not be high enough to be a real deterrent. $200/square metre equals $18.50/square foot. A quality green roof, complete with an irrigation system, beefed up roof deck to support the extra load, and annual maintenance has a net present value of well over $30/square foot, even if one includes slight energy savings during the cooling season, and increased roof membrane service life. In fact, a green roof alone costs about $25/square foot. All building owners will save money by paying the fine instead of installing a green roof.
 

T.O.Fanatic

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Not a bad idea, although this council really doesen't have a concentrated environmental plan, they just come out with random policies, would be nice to have real vision for a change.
 

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