User login

A Community of Green Bloggers & Activists

Case Study of the Dangers of Green Roofs

Stephen Del Percio of the Green Real Estate Journal recently wrote about some of the dangers connected with green roofs, particularly installation of uneducated project teams. In the article he cites a story by Kelly Luckett, the "Green Roof Guy" of

The story goes that a Toronto based team, in which Mr. Luckett was a part of, installed a green roof in 2008. The owner of the premises where the installation occured decided to disconnect the irrigation sytem after the intial establishment phase at the urging of another contractor. The contractor convinced the owner that the irrigation was not neccessary because of the climate of Toronto. By doing this the owner would achieve LEED certification.


Case Study of the Dangers of Green Roofs

As time progressed the owner was quite suprised by the withering of the roof. This caused the loss of over $250,000 of vegetation. Recalling the intial conversation between the owner, the contractor and himself, Mr. Luckett was astonished by the response of the contractor. "The owner’s representative placed in charge of one the city’s largest green roofs, in arguably the most green roof educated city in the nation, was utterly surprised by the fact that plants need food and water."

I do agree with Mr. Del Percio that this highlights problem with the fledgling green roof industry, specifically the lack of knowledgable contractors and the failure of adequate codes regulating the industry. I do believe this is a valid point, but not insurmountable. Simple legislation on a city or state level will alleviate these issues and adequate checks of experience could solve the issue. Most importantly for this situation is education. Owners of green roofs must understand maintenance is necessary for any green roof to be successful and this requires WATER. Thus, don't disconnect your irrigation system. What do you think of this issue?




green roof irrigation

Note that in many climates, irrigation is recommended for just the first 1-2 years until the plants are established. Extensive green roofs are designed to be low maintenance and to use vegetation that can survive in roof (harsh) conditions. Any reputable installer will require that they cover the first 2 years of maintenance to avoid exactly this issue. If your installer does not require a 2 year maintenance contract (and maintenance is minimal but there are weeds until the plants have coverage), get a new one and insist on this in the contracting.

Case Study of the Dangers of Green Roofs

I could name 25 or more projects like that.

Since the green roof industry started in the North America I realized that many people in this business are just looking for the big and quick bucks. They come from all kind of professions and hardly have any fundamental and long-term practice with hands-on experience in landscaping plus horticulture. They don't have any passion.
The ignorance of the North American people to well establish green roof guidance from Europe with the decades of green roof experience (more than 30 years) is an additional factor for many failures of American green roof projects.
The problem starts with the designers/architects continues with consultants, suppliers, general contractors, subcontractors, building owners and closes with governments, cities, Unions and associations.
The system in North America makes it very easy that - for example - a butcher, driving instructor, plumber, mechanic, student or just a talker etc. can get a sort of certification in green roofs consulting in less than 3 days. Sometimes it is even enough having some sort of plants related background or sort of "green" history and you are accepted as a green roof expert. Another big bummer in America is that on each project there are too many people involved and too many want to say something. This drives the costs up and reduces the responsibility of a single person or company at the same time = nice breeding ground for failures.
I am not complaining – I am taking advantages of the system, too.
By the way and don’t listen since I am from Europe: If you do an extensive green roof in Toronto right -from the beginning- you don’t need irrigation.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.