Saving the Planet with your Green Roof

Saving the Planet with Your Green Roof


Environmentalism has long ceased to be just a grassroots movement. Today, more and more people are waking up to the fact that the planet must be taken care of through meas-ures big or small. With more people commit-ted to reversing or minimizing the damage to our ecosystems, movements like sustainable building are popping up, equipping properties throughout the country with practical building solutions that tread lightly on our environment.

Green roofs or living roofs are an offshoot of this sustainable building philosophy. Featuring vegetative layers that range from simple two-inch hardy groundcovers (extensive) to fully accessible rooftop parks (intensive), these roof systems pack a powerful punch of sus-tainable, eco-friendly functionality. When you live or work under one, you’re being protected from the elements by a roof that proactively

helps the environment every single day.


Part 1:

Air Quality


The heat island effect is a phenomenon marked by the noticeable difference in temperature between highly urbanized areas and the surrounding suburbs and rural communities. This effect comes with a number of adverse consequences for the inhabitants of big cities and met-ropolitan areas—such as increased energy consumption (especially in the warmer months) and higher levels of greenhouse gas production and air pollution.

Green roofs have proven themselves effective in mitigating the heat is-land effect by virtue of the air-filtering capacities of plants. Thanks to their greenery, these roofs are able to remove particles and organic compounds in the air that act as cat-alysts for ground-level ozone (smog) production, a chemical reaction further aided by high temperatures. The result? Less heat trapped and better air for you, your neighbors, and the whole community.

In addition, analyses of air samples in communities with a large number of green roofs show a reduction in the amounts of sulfur dioxide and nitrous acid—compounds central to the production of acid rain.

Bonus: The removal of noxious gases and other pollutants from the atmosphere is also indirectly linked to better water quality. Green roofs retain the pollutants they have filtered out of the air and curb surface run-off, effectively keeping the bad stuff out of your water supply.

Image: Green roof planted with native species at L’Historial de la Vendée


Part 2:

Biodiversity


Green roofs’ vegetative layers do much more than just beautify your property; they are designed to be systems of substrates and microhabitats that support life. In communities that have already gone through a series of development projects, these microhabi-tats are even more essential. It is no secret that land development plays a huge part in wiping out large populations of insects, birds, and wildlife. Your green roof can help link wildlife corridors, stabilize dying ecosystems, and fill your community with new life.

▶ Soil substrates as growth mediaEngineered soil mixes meant for green roof use aim to mimic the components of natural soil with the goal of sustaining vegetation. They are able to simulate many of soil’s life-building characteristics, such as water retention, erosion control, permeability, and density.

▶ Stepping-stone habitats for displaced & migrating speciesA carefully nurtured green roof microhabitat can act as a supplementary ecosystem for species that have been displaced from their natural surroundings as well as for those that are migrating.

Apartment complex in Tongyang Town, Tongshan County, Hubei


Tip: Careful planning is important in properly har-nessing the life-supporting functions of your green roof. To this end, it pays to study the ecological conditions in your area and to consult a professional for the successful design, implementation, and construction of your roof.

An Ecological Journey: Examples of Green Roofs That Support Biodiversity

▶ The green roof in the Goodwood plant, a Rolls-Royce factory near Chichester, West Sussex, is fa-mous for being a second home to breeding skylarks.

▶ National Geographic called the 20,000-square-foot green roof atop the Vancouver Public Library ”a prairie, not an asphalt wasteland”.

▶ Seattle’s Ballard Library has a green roof that sus-tains 18,000+ low-water-use plants, such as blue-eyed grass, wild thyme, Oregon stonecrop, and more.

▶ The California Academy of Sciences boasts a 2.5-acre green roof covered in native vegetation, which provides a habitat for local species like the federally threatened Bay Checkerspot butterfly.

The California Academy of Sciences, Golden Gate Park, San Francisco, California


Part 3:

EnergyEfficiency


So living roofs clean the air and help form thriving ecosystems. Any eco-conscious property owner would already be sold, right? But it gets better. The rising popularity of green roofs largely stems from their ability to significantly cut down energy costs in homes and commercial buildings. With your green roof, you will not only breathe fresher air and create a habitat for different plant and animal species, but also dramatically reduce your own carbon footprint

and save money in the long run.

you will not only breathe fresher air and create a habitat for different

plant and animal species, but also dramatically

reduce your own carbon footprint and save money

in the long run

“

“

Traditional sod roofs can be seen in many places in the Faroe Islands.


Growing a layer of greenery on your roof minimizes the impact of solar heat on a home or building’s internal tem-peratures by two different mechanisms, namely:

▶ INSuLATIONTraditional roofs are exposed to direct solar radiation, which leads to high internal temperatures especially dur-ing summer. By providing added insulation, multi-layered green roofs increase your property’s thermal efficiency, which takes a huge load off your cooling systems. The extra insulation also helps during the cooler months by minimizing heat loss through the roof.

▶ PLANT ANd SOIL ACTIONPhotosynthesis, evapotranspiration, and soil evapo-transmission—processes by which water moves through plants, soil, and air—work together to form a natural cooling mechanism for your property. The end result is cooler temperatures in the living and work spaces under a green roof and a reduced need for air conditioning.

What does this mean for your home or building?

▷ Lower utility bills.▷ Longer life expectancy for your heating, cooling, & ventilation systems.

▷ Possible tax energy credits.

What does this mean for your community?

▷ Reduction in urban heat island effect.▷ Better resource allocation.▷ More successful energy conservation policies.

Bringing Environmentalism Home

Environmentalism does not have to be a big concept possible only through specialized practices. It can start with you, right in the comfort of your own home. Make a green roof your first step. The whole planet will thank you.

Sources:http://energy.gov/energysaver/articles/tips-energy-efficient-roofshttp://www.epa.gov/heatisland/mitigation/greenroofs.htmhttp://www.efb-greenroof.eu/verband/fachbei/fa01_englisch.htmlhttp://www.greenroofs.com/Greenroofs101/growth_media.htmhttp://www.greenrooftechnology.com/green-roof-typeshttp://www.greenroofs.org/index.php/about/greenroofbenefitshttp://ngm.nationalgeographic.com/2009/05/green-roofs/klinkenborg-texthttp://en.wikipedia.org/wiki/Green_roof#united_Stateshttp://en.wikipedia.org/wiki/Bay_checkerspot_butterflyhttp://fmlink.info/article.cgi?type=Benchmarking&title=Green%20Roofs%3A%20A%20Sustainable%20Solution%20for%20Energy%20Savings&pub=Facility%20Issues&id=40525&mode=sourcehttps://www1.eere.energy.gov/femp/pdfs/fta_green_roofs.pdfhttp://www.efb-greenroof.eu/verband/fachbei/fa01_englisch.htmlhttp://en.wikipedia.org/wiki/Green_roofhttp://en.wikipedia.org/wiki/California_Academy_of_Sciences

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Saving the Planet with your Green Roof