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If green roofs were mandatory in cities would there be less development and building?
William McDonough knows the benefits that come from designing and implementing green roofs. McDonough has helped design living roofs for big companies such as Nike and Ford Motors. But many companies and homeowners overlook the benefits of green roofs. One benefit of green roofs is that they keep the internal temperature of a building steady throughout the year. The National Research Council of Canada found that having a green roof reduced the daily energy demand for air conditioning in the summer by 75%. Toronto is the first North American city to pass a law mandating green rooftops for all new residential, commercial and industrial developments. Any new construction with floor space of more than 2,000 square meters must devote between 20 and 60 percent of its roof to vegetation. But with green roofs comes an unwanted financial upfront cost. Will developers decide that the benefits outweigh the costs for installing green roofs?
If green roofs were mandatory in cities would there be less development and building?














Debra Smith 200+
Many people will not vounteer for a prosocial behaviour but when it becomes mandatory they make the best of it and adapt it to their own purposes so that they do not appear to have been maliable to authority figures. Did you ever notice how many people compost now that recycling is required?
Allison Walter
Casey Gibbons
Theresa Berkovich
Allison Walter
Stephanie Loredo
Eric Parsons
Matthew Kinsella 50+
Molly McDevitt
Matthew Kinsella 50+
Stephanie Loredo
Theresa Berkovich
Beatrix Bacher
Patrick Mazi
Christina Thommes
Kadie Hayward
Andrew Moore
Molly McDevitt
Andrew Moore
Alexa Westerbeck
Matthew Kinsella 50+
Em Crawford
Amanda Hooper 50+
Nickie DeReu
Lisa Murphy
Heath Jones
Alexa Westerbeck
Nickie DeReu
Logan Hein
Wayland Tan
As you go higher up, it would stand to reason that there would be a selection for organisms in their ability to reach up to the higher stories (probably mostly birds) and whatever else that may be brought up there by humans (again, whether they be on purpose or accidental).
That actually sounds like a cool experiment to conduct. 'Would you find a general trend of losing biodiversity as green roofs go to higher elevations?' or something in that line of thought. I wonder if anyone has thought of testing that out?
It might also depend on what type of plants people want to grow up there, such as purely aesthetic plants, or as people have mentioned before, garden plants for growing food.
Beatrix Bacher
I don't think that this would necessarily hinder building development, although in my opinion we could do with less individual homes instead building urban areas upwards to increase density and get rid of suburbia. People may not be willing to pay the extra costs, some may not believe that it will save them heating/cooling costs and others may consider it a hazard, but I think if they became mainstream and all new houses were equipped with them then there would be less resistance.
Debra Smith 200+
Allison Walter
Dan Stark
The effect of compelling producers to add a new component to each of their products is that the cost of production rises. The result is that the marginal producers -- those whose costs have now been driven higher than the revenues they can obtain from the product -- are driven out of business. We end up with reduced supply and a higher market price, which in turn leads to the marginal buyers -- those who were prepared to pay the original price but not the new, higher one -- investing elsewhere, e.g. in other cities.
Now, of course people can freely purchase a green-roof building, and they will do so if the savings on air conditioning and the other benefits of such a building outweigh the additional cost -- in short, if the choice is economical. Thus we arrive at the conclusion that if green-roof buildings are economical, a government mandate is irrelevant; and if they are not, it's harmful (reduced production and higher prices).
This conclusion should really just be common sense: social wealth and well-being can't be increased by ordering the police power to forcibly prevent people from engaging in voluntary exchange.
Ellen Ingamells
Mat Lisin
I think in certain areas green roofs are a brilliant idea, in Portland for example I would love to see this law implemented. I don't think that requiring green roofs all over the country is a good idea. I think the government should offer incentives to cities to enact this law on their own, but leave it up to the city (or maybe the state) to decide whether they require green roofs. These more local governments should look into what would help their area the most.
Ellen Ingamells
Matthew Nelson
I agree with Mat that the movement of water up a building is a terrible waste of energy and water, which is scarce in the desert as is, and Ellen is right that the flora should be native. A national law mandating green roofs, however, will just mean more "inequality." The Northwest will build the desired "green" roofs while Arizona grow their cacti. I wouldn't have it any other way, but this federal law would meet endless resistance if any part of it mentions native plants. We like to design landscapes that oppose nature rather than work with it and many parts of America would oppose their native plants as fixtures for their green roofs because they don't find them aesthetically pleasing. I think a policy such as this would only work at the municipal level.
Em Crawford
Olivia Hurd
Mat Lisin
Also little to no maintenance? Not to harp on this solar thing, but they require little to no maintenance. I just don't see how plants baking in the sun all day could possibly not require maintenance. Again, I'm speaking with regards to certain areas. In the PNW I'm sure the plants would require little to no maintenance and would be a better solution. I don't mean to say I think we should change the idea to solar roofs instead of green roofs, I just think solar may be a better way to go in certain areas.
Olivia Hurd
Logan Hein
geoffrey douthat
but they r cool, funny how green roofs came before green walls, makes me wonder how the roof was held up... ha
Georgia Kurtz
Drew Thompson 50+
Eric Parsons
Katie Bergus
Bre Senate
Tina Zhu
Drew Thompson 50+
Tina Zhu
Christopher Tam
Drew Thompson 50+
Sarah Caponi
Jorge Contreras
Heather White 20+
In the UK (before the economic slump) many local authorities were selling allotments to developers (there is a massive housing shortage in the UK). Even today allotments are at risk as LA's sell as many assets as they can to preserve local services. This is at a time when pensioners and the unemployed would benefit from having access to land - not only to provide food for themselves and their families, but also to stay fit, active, empowered and connected with people in their communities. Perhaps we could have community allotments at roof level on all governemnt and commercial buildings. Instead of the WW2 "Dig for Victory" campaign we could have a "Dig out Austerity" campaign.
Lauren Hawkins 50+
Nathan Heidt
Morgan Grove
jag . 50+
Kirsten Gotting
Nathan Heidt
Kirsten Gotting
Heath Jones
Rishi Patel
Billy Brennan
There are places where this would just not be practical however, including areas with high winds, extreme temperatures, and lack of rain. I am not aware of any down sides of green roofing, and am very interested to hear more critiques because it seems like a sure fire great idea to me in most places.
Steve Means
I did want to say a bit about building codes, and law in general (again, see discussion below). The building code in California is montrous and therefore impossible to properly enforce (and therefore only about 80% followed). I really think most codes could be dramatically simplified so that they would be better followed (psychotic corporations will fight this idea tooth-and-nail). For example, all of California's Title 24 Part 6 could be replaced by something like this: "There will be no further gas or propane hookups except at commercial kitchens, and only a single 20 Amp electtrical supply per residence or 10,000 sqft of enclosed floor area." That puts our priorities about where they need to be, and is extremely simple to interpret and enforce. A similarly simple set of rules could be promulgated for water (which is not covered by Title 24 Part 6).
Lauren Hawkins 50+
Trevor Howard
Kathleen Kearns
Christina Thommes
Katie Bergus
Wayland Tan
On a brighter note, I believe that there have been cases where, instead of putting huge fines on people for failing to match up to certain environmental standards, if there are smaller, more manageable fines, people are more prone to respond to it.
So perhaps a good way to make this come about is to have small fines or taxes for the buildings unable to live up to code, while at the same time give subsidies (like how the govt. gave subsidies for highways and freeways) for the construction of green roofs.
Brooke Bilyeu