Green Roofing and Rooftop Gardens:
Beautiful and Beneficial

Green roofing and rooftop gardens - We have all seen them and had one of three reactions:

"Wow!Look at that beautiful penthouse rooftop garden; I could definitely live HERE!"
"OMG! How did they manage to grow THAT on their roof? Look at all those beautiful birds and butterflies, I wonder if I could do that on Rover's doghouse?"
"Boy, that's clever! If we can design these roofs in all urban areas, we can probably grow fresh organic food, get clean air, and even insulate the buildings!"

Ok, maybe those weren't *exactly* what you were thinking, but something like that(?).

There is a lot to say about this type of roofing, they are clever, they can be very attractive (or pretty ugly), and they need some front-end work with major residual payoff.

Having soil and vegetation that grows on a roof may sound unconventional, but green rooftops have been used for hundred of years. Today, green roofs are usually planted over a flat or low pitched roof membrane that can withstand standing or ponding water. These roofs have to be waterproof and can incorporate rain water harvesting (or water drainage for collection and irrigation).
Container-Fulls of Social, Natural and Environmental BENEFITS:

Increase the usability and livability of your home by claiming more "productive space".

Increase physical and mental health by providing more natural beauty.

Reduce the "urban heat island effect" - this refers to the higher temperatures that result from blacktop or tar surfaces that increase the surface temperature of an area (usually in urban settings).
If you look at a heat map generated by a satellite, for example, you can clearly see several degrees of temperature rise in cities and surroundings.

These temperature differences cause air currents, dust, and even contribute to localized weather events. Green roofing helps cool and slow the air. The plants are also an excellent sink for pollutants to settle, helping clean the air.

Reduce noise by as much as 40 decibels. Soil, plants and air are great insulators.

Reduce storm water runoff. This is a multi-pronged advantage. First, the rainwater is absorbed in the plants, and helps reduce the stresses on a municipality's storm drainage system, saving money. Also, defraying costs for building water management systems helps offset the costs of the green roofs.

When used with rainwater harvesting systems, vegetated roofs help with water conservation. Also, as water percolates through the roof plants filter water, removing nitrates, and other pollutants from acid rain.

Here's the real beauty for all of us commuters (and telecommuters!); any runoff usually takes place after the peak event - meaning reduced flash floods - giving sewer systems the ability to handle the runoff from impervious surfaces.

What an elegant solution to several environmental issues!

How is It Done?
You can set it all up yourself - there are many sites available with instruction on how to prepare your roof, what types of plants to use, and how to grow and maintain your plants. Typically, the recommended plants are low-lying, drought-resistant varieties - sedum seems to be a favorite though.

If you have a flat roof that will be used for entertaining, you can landscape it with all types of indigenous plants and flowers. Live roofs takes work, and maintenance, otherwise, you will end up with rot and other issues, including overgrowth, browning, leakage, and - dare I say it - uninvited guests/pests.

Do a bit of reading at the following website: greenroofs.org. It is not only informative and interesting, but absolutely inspiring. Whether you decide to do-it-yourself, or hire a pro, you will get a good idea of efforts and costs. For ready-made, pre-vegetated roof garden or green roof kits, I have come across a LEED-certified company, called liveroof.com which provides residential and commercial services. There are many out there, use the search box on the top right corner for "diy green roof kits".

For an interesting and easy approach as a first test-bed green roof (on a shed), check out the green roof video below by a New England nursery. This doesn't give you a step-by-step approach, but shows how doable the project is.