Guest Post by Matt – Reilly Roofing
Long popular in Europe, green rooftops have begun to appeal to U.S. homeowners, businesses and even cities as an attractive way to promote environmentalism while solving the problems of conventional roofs. A green roof supplements traditional vegetation without disrupting urban infrastructure — they take a neglected space and make it useful. Today it’s clear: vegetated roofs offer many social, environmental and economic benefits.
What is a Green Roof or Living Roof?
Plants have been used on roofs for thousands of years, from sod roofs in Europe to the hanging gardens of Babylon. But in the last 50 years, this practice has evolved into what are now called green roofs, living roofs or eco-roofs. Green roofs are those that have been planted with specific vegetation using a well-researched sustainable design methodology. They are an exciting new development in the sustainable building movement and are gaining in popularity across the world.
Here are some of the benefits of living roofs:
• They last longer than conventional roofs
• Green roofs reduce energy costs with natural insulation
• A peaceful retreat is created for people and animals
• The green roofs absorb storm water, potentially lessening the need for complex and expensive drainage systems
On a wider scale, green roofs improve air quality and help reduce the Urban Heat Island Effect, a condition in which city and suburban developments absorb and trap heat. The layers of a green roof must, like any roof, accommodate drainage and protect the building from the elements with a waterproof membrane. But they also must create a growing area and potentially provide support, irrigation and root protection barriers while staying as light as possible.
Depending on load capabilities and other application-driven requirements, green roofs can be planted with herbs, grasses, flowers, even trees, in an exciting variety of colors, textures, scents and heights.
Year Around Savings Potential of Green Roofs
The exact amount of savings is difficult to calculate, as utility costs vary from state to state. “The savings comes from reduced utility costs and even reduced [roof] maintenance over time. But the green roof has to be properly installed and inspected from time to time.” (Source: Sarnafil)
According to the National Research Council of Canada, a green roof can reduce air conditioning demand in the summer by as much as 75%. It should have no more than a 20-degree slope, if not lower.
Green roofs prolong the life of the roof underneath it. They protect the roof from the sun, which can wear it down, and from snow and rain. They have been proven to increase the length of roof life. Patios and walkways can also become a usable part of the roof environment.
Key environmental benefits of green roofs:
• Reduce storm water run-off which, in turn, reduces the stress on urban sewer systems and decreases run-off related pollution of natural waterways
• Insulating qualities mean reduced energy costs for building owners
• Air quality improvement – lower rooftop temperatures mean less smog from the “urban heat island effect”
• Noise pollution reduction – studies show noise levels in a building can be reduced by as much as 40 decibels
• Extended life of the roof system due to moderated temperature swings that cause a roof system to expand and contract as well as protection from everyday wear and tear
• Reduce the need for air condition and thus reducing greenhouse gas emissions.
– Learn more at Sarnafil.
Summary: Benefits of Green Roofs
As you have read, there are a number of social, economic and environmental benefits to green roofs. Here is one last look at those benefits:
– Increasing home energy efficiency – cooling in summer, insulation in winter
– Filtering and cleaning toxins from both air and water
– Reducing carbon dioxide emissions
– Retaining rainwater before it evaporates, reducing the likelihood of flooding
– Reducing urban temperatures and associated smog
– Insulating against sound and noise
– Preserving and enhancing biodiversity
– Providing aesthetic appeal and ‘green space’ recreational opportunities
– Using recycled materials like aggregates and plastic sheets
BIO: With a background in construction and green technology, Matt works both as a writer and the new editor for the Reilly Roofing & Gutters Blog. Throughout his work, he promotes the sustainability movement and the use of eco-friendly technology in everyday life.