A green roof in Doral is known by several names such as ecoroof or living roof. They have been built on buildings for centuries. Many countries in the world have green roof subsidies or programs that encourage ecoroofs. Scandinavia has long had farm house buildings that have sod covered roofs. Some cities in the US are known for their living roofs such as Chicago’s City Hall building.
Basically a green roof is a roof that has vegetation and a growing medium. It will cost more than a standard asphalt shingle roofing application. Rooftop garden costs also depend on the type of green roof installed. There are several differences among green roofs in Doral and some applications that may or may not be defined as a green roof such as a container garden green roof.
What Is Green Roofing?
Sustainable, or "green," buildings - buildings that are deliberately designed to use natural resources in a way that's environmentally friendly -- are no longer a luxury. They are an imperative.
Consider the facts: According to the National Institute of Building Sciences' Whole Building Design Guide, "On an annual basis, buildings in the United States consume 39 percent of America's energy and 68 percent of its electricity. Furthermore, buildings emit 38 percent of the carbon dioxide (the primary greenhouse gas associated with climate change), 49 percent of the sulfur dioxide, and 25 percent of the nitrogen oxides found in the air. Currently, the vast majority of this energy is produced from non-renewable, fossil fuel resources..."
Of the two ways to reduce heating, cooling and lighting loads "through climate-responsive design and construction practices," the Whole Building Design Guide recommends the use of "high-performance building envelopes: select walls, roofs, and other assemblies based on long-term insulation, and durability requirements."
One of the most sustainable, high performance building materials prevalent throughout the world is zinc.
Zinc is reported to be the 23rd most abundant element in the earth's crust. It is a non-ferrous metal that is not susceptible to rust or corrosion: It's weatherproof, seismic proof, corrosion resistant, and immune to the harmful effects of UV rays, ensuring a very long service life without degradation.
This is possible because architectural zinc develops its own protective layer, which is called zinc hydroxyl carbonate. Once it's formed, that layer blocks moisture and chemicals from penetrating the zinc and, if it's scratched, the hydroxyl carbonate will reform over time. In other words, zinc heals itself. That's why zinc walls and roofs last on average from 80 to 100 years.
Zinc also requires very little energy to manufacture and little to no maintenance, and it is 100 percent recyclable from new construction scrap to the time it reaches its end use. As a result, zinc roofs and wall cladding never end up in landfills.
For generations, European architects have specified zinc as a building envelope material for all types of buildings because it would last and endure harsh weather conditions. In the late 1700s, zinc was also one of the most popular materials used for roofing in America, which is why many well-known historic structures, such as the Washington Monument and Thomas Jefferson's Monticello, had metal roofs.
Unfortunately, zinc fell out of favor in the U.S. as less expensive roofing materials evolved, such as asphalt shingles, and as American developers and building owners lapsed into a "throw-away" mind-set in the 1960s and '70s that still assumes no more than a 30- to 50-year life span for American buildings.
Today, American architects are becoming more enamored with the material, not only for its durability but also because of the increasing need for environmentally sustainable design and construction.
American architects are warming to the use of zinc on commercial, institutional, and government buildings. A few far-sighted practitioners are also encouraging their residential clients to use architectural zinc on their homes - from brand-new construction to renovation and historic restoration.
New Construction: Thinking of The Future
"Zinc ultimately costs much less than asphalt shingles when you calculate the life span of the house," says Daniel Nicely, director of market development for VMZINC and an associate member of the American Institute of Architects (AIA). "Shingles are usually composed of asphalt, a decidedly non-green material, and an average shingle roof will need to be replaced about every 10 years -- four to five times compared to the lifetime of one zinc roof."
The value of zinc's low maintenance factor was underscored at the University of North Carolina at Greensboro when the decision was made to use zinc for two projects there, including the Hall for Humanities Research and Administration. The university acknowledged that construction budgets tend to be well funded but maintenance budgets are not. The self-healing characteristic of zinc was another factor in the decision, as was aesthetics:
"Zinc worked well because of the appearance," said Andy Sykes of Calloway Johnson Moore & West, PA, in North Carolina, project manager for the Hall for Humanities' project. "The color was more similar to what historical turn-coated lead roofs looked like and blended with the traditional campus roofs." (source: McGraw-Hill Construction, Continuing Education Center)
The aesthetic quality of architectural zinc for historic buildings was a key issue for the Central Presbyterian Church in Huntsville, Alabama, when it renovated the Cooper House, a nearby antebellum house that is listed on the National Register of Historic Places, to become its new Family Life Center. The old house needed a new roof and rainwater system that would be consistent with the house's historic style and last well into the future.
Hays Buchanan, the architects on the church project, chose natural VMZINC "for its historically correct gray color, strength and durability," reported Design & Build With Metal.com recently.
While zinc is often used in contemporary applications, the Cooper House project is a perfect example of why it is is a natural choice for historic restoration: the color, in this case of natural VMZINC, is historically correct aesthetically pleasing, durable and intended to last for decades. In addition, production techniques allow it to maintain the unique look of natural metal with consistent colors. Natural VMZINC will not develop a drastically different patina like copper, for example, that changes from its copper color to green. Instead, it weathers over the years to form a textured gray patina.
Design and Build with Metal.com also reported that Central Presbyterian church leaders and the Huntsville/Madison County Historical Society "readily approved the application [of zinc roofing and rainwater system] as consistent with the building's historical architecture."
Will Residential Use of Zinc Sweep America?
After rhapsodizing over the beauty, value, and sustainability of architectural zinc, Dallas architect Bob Borson answered the question he knew his blog readers would ask: Why isn't zinc used more in residential design?
"The reason we don't use it more often is because of the price," Borson wrote. "For the average standing seam profile, material cost and labor will run you in the ballpark of $20 per square foot."
For a young family building their first home, or senior citizens replacing the roof of a home they've already lived in for over 50 years, the cost is understandably prohibitive. But for new, modern homes from North Carolina to California, elegant estates in the North East or Pacific Northwest, a mid-century or old farmhouse renovation in Florida or Kentucky, or a historic home in heart of Charleston, Savannah, New Orleans' French Quarter, et al, the durability and sheer beauty of zinc roofing and wall cladding will continue to gain popularity as the imperative for sustainable, energy-saving homes grows stronger.
How Green Roof Systems Save Your Business Money on Heating and Cooling
Before I became involved in the world of green building I had never even seen an eco-roof. The first time I saw one it struck me that from a purely aesthetic or architectural point of view they create a sense of integration, or synthesis between the structure and the surrounding landscape, but that isn't even the half of it...
I had the pleasure of interviewing Rosalind Haselbeck who along with Richard Alianelli form Building Green Futures, a San Diego company that specializes in living roof installation, here's what she had to say;
BIGC- So what do you see as the chief benefits of a living roof?
BGF- The answer to that depends on your idea of 'beneficial' I would say the greater benefit lies in the many environmental aspects, such as the regained space for plant life (pollution and CO2 reduction) as well as mitigation of the urban heat island phenomenon. However for the individual property owner his immediate and personal benefit lies in the exceptional insulation, and temperature reduction/stabilization effects, as well as improved storm water management due to the absorptive qualities of the growth medium and plant life. Did I mention they are beautiful?
BIGC- And maintenance?
BGF- That varies depending on type. Generally you would maintain your green roof twice a year, weeding, clearing drains, fertilizing- the same sorts of things you would do with your regular garden or landscaping...only on your roof.
So there you have it from the horses mouth. There are many factors involved in the world of green roofs. It all comes down to what is right for you and your budget. The good news is that there are now professionals out there like Rosalind and Richard who have made it their business to green the roofs of the world.
P.S. If you want more info check out these Cool Green Roof Links)