How green was my roof

As "sustainable architecture" becomes a familiar term to many, we're starting to hear a lot about green roofing. It's a concept that seems to have an awful lot going for it, and -- added bonus -- it looks really cool, to boot (especially from a Google Earth POV). Via Ecogeek, here's a quick primer on just what they are and how they work.

First of all, there are two kinds of green roofs:
intensive, which are between two and four feet deep and support the growth of all kinds of plants and even some small trees, but require a great deal of structural support, because they're really heavy, and
extensive, the most common kind of green (or "vegetated") roof, which are about four inches deep at the most. Many kinds of grass and drought-resistant plants can thrive at that depth, which also naturally limits weed growth and tends to self-regulate. (Naturally, their weight is also a lot easier to support.)

The benefits
There are many, but a few of the most compelling include

Keepin' it cool:

Green roofs keep the roof cooler, which helps to reduce the heat-island effect, which contributes to cities being hotter than the surrounding countryside. This can be beneficial to the building in reducing its summertime cooling load.

Longer roof life:

Green roofs also protect the roof membrane from sunlight, which breaks down the roofing material. Having even a couple inches of soil helps to greatly extend the life of the roof, and a longer lifespan means less material ends up in landfills from re-roofing buildings after the membranes have failed.

Greatly reduced stormwater runoff:

In some cases, this can help reduce the size of stormwater pipes, and the amount of stormwater that needs to be treated by municipal water treatment. In a light rainfall, a building with a vegetated roof can have no stormwater runoff at all.

Everybody gets a yard:

In cities where concrete rules and green space is at a premium, how cool would it be for everyone to have a little park of their own on the roof? You can BBQ up there, stretch out for a nap in relative peace and isolation, and even, as some have done, graze farm animals!


The drawbacks
Right now, the main drawback is expense. It's definitely pricey to convert an existing "normal" roof to a vegetated one; the extra load necessitates extensive surveying and architectural rejiggering (and architects drive fancy cars for a reason). Cost is less of an issue with new construction.

Picture credits:
1) Green roof in Oswego, Illinois by Greg Robbins. Greg Robbins on Flickr
2. Goats grazing on a roof in Wisconsin, from Driftless Media on Flickr

Quick True/False: World Capitals
Bain News Service - Library of Congress, Public Domain, Wikimedia Commons
10 Pats Born on St. Patrick's Day
A photo from the 1919 wedding of Princess Patricia of Connaught to the Hon. Alexander Ramsay.
A photo from the 1919 wedding of Princess Patricia of Connaught to the Hon. Alexander Ramsay.
Bain News Service - Library of Congress, Public Domain, Wikimedia Commons

Need some St. Patrick's Day conversation fodder that doesn't involve leprechauns or four-leaf clovers? Ask your friends to name a "Pat" born on St. Patrick's Day. If they can't, they owe you a drink—then you can wow them with this list of 10.


Princess Patricia was the granddaughter of Queen Victoria, who gave up all of her royal titles when she married a commoner. She was born at Buckingham Palace on March 17, 1886.


The Dallas star was born on March 17, 1949. And here's a totally random fact about Duffy: His nephew is Barry Zito, former MLB pitcher for the Oakland Athletics and the San Francisco Giants.


Pattie Boyd
Larry Ellis, Express/Getty Images

Pattie Boyd is well-known to lovers of classic rock: She has been married three times, including once to George Harrison and once to Eric Clapton, who both wrote a couple of the most romantic songs in rock history in her honor (including The Beatles's "Something" and Clapton's "Wonderful Tonight"). Boyd was a model when she met Harrison on the set of A Hard Day's Night in 1964; the pair were married two years later. They divorced in 1977 and she married Clapton, Harrison's close friend, in 1979. She also had an affair with Ronnie Wood of the Rolling Stones toward the end of her marriage to The Quiet Beatle.


Belfast-born Pat Rice is a former footballer and coach who spent the bulk of his career with Arsenal F.C. (that's "football club," a.k.a. soccer to us Americans). He joined the Gunners in 1964 as a mere apprentice, turning pro a couple of years later. He became captain in 1977 and left the club for a few years in the early 1980s to go to Watford, but returned after he retired from playing in 1984. In 2012, after nearly 30 years with the organization, he announced his retirement.


Patty Maloney is an actress with dwarfism who stands just three feet, 11 inches tall. She has appeared in many movies and T.V. shows over the years, including operating the Crypt Keeper puppet in Tales from the Crypt. She also played Chewbacca's son Lumpy in The Star Wars Holiday Special.


Michael C. Hall and Mathew St. Patrick in 'Six Feet Under'

Ok, so Mathew St. Patrick is the stage name of the actor, but he was born Patrick Matthews in Philadelphia on March 17, 1968. You probably know him best as David's boyfriend Keith on Six Feet Under.


He may not be a household name, but the recording artists Patrick Adams writes for and helps produce certainly are. Adams has been involved in the careers of Salt-N-Pepa, Sister Sledge, Gladys Knight, Rick James, and Coolio, among others.


It's possible you look at Patrick McDonnell's work every day, depending on which comics your newspaper carries. McDonnell draws a strip called Mutts featuring a dog and a cat named Earl and Mooch, respectively. Charles Schulz called it one of the best comic strips of all time.


 Singer/Guitarist Billy Corgan of Smashing Pumpkins performs onstage during Live Earth New York at Giants Stadium on July 7, 2007 in East Rutherford, New Jersey
Evan Agostini, Getty Images

Yes, you know him better as just plain old Billy Corgan: he's the face of the Smashing Pumpkins, engages in public feuds with Courtney Love, and maybe once dated Jessica Simpson. He made his debut on March 17, 1967.


Patricia Ford is a retired model probably best known for her Playboy photoshoots in the 1990s.


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