written by:
March 1, 2013
If you live in a large metro like we do, odds are you see mostly bleak-hued buildings. Lots and lots of buildings. One thing we don’t see enough of? Greenery. Of any sort, really. (Unless you count the dog park, or rather, the patch of brown grass down the street.) We’re so nature-deprived we’d welcome the sight of some weeds.

Why go with a green roof? This infographic calculates costs versus benefit and gives tips (hint: chickens) on how to maintain grassy perfection.

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Movato Real Estate Blog
This article was originally published on February 20, 2013 on Movato Real Estate's Blog.
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greenroofinfographic pt 1

Why go with a green roof? This infographic calculates costs versus benefit and gives tips (hint: chickens) on how to maintain grassy perfection.

green infographic 2

green infographic 3

Lucky for us though, we recently came across the perfect solution for our green-deficient misery: green roofs.

Plant them on your roof and the top of your home becomes your very own grassy plain; convince the super next door to grow one and you’ll have the perfect view of faux fields to wake up to. (Our apologies if you’re surrounded by tall buildings.)

And the best part of using your roof as an alternative to a yard? After installation, it’ll require less upkeep and positively impacts your electric bills (more on that later).

movato blog green1

A rooftop yard also means you need to haul less grass home than for a more traditional lawn—our version is only a third of the typical yard size, or 2,625 square feet of grass.

If you’re wondering how a green roof means less maintenance work for you, then ponder no longer. A number of pet-friendly animals eat grass, and naturally we figured we could kill two birds with one stone by employing our pets to trim our rooftop lawn.

By our math, we could feed 70 feathered fowl in a single day, or 105 guinea pigs.

You’re starting to get on board now, right?

Mossy Roofs–The Fashion Statement for Your Home

Before we leave you to your own gardening devices, we should give you a bit more information on these eco-friendly gardens of a different level (hardi har har).

To start with, turning your roof green is basically the hot new thing to do to prove your devotion to Mother Earth. (Though technically they’ve been around for ages, literally–sod roofs were popular in Norway during the Middle Ages.)

The California Academy of Sciences in San Francisco has one; Walmart has been building the eco-friendly feature on some of its newest stores; and Chicago boasts the world’s largest green roof (but it’s not in the Guinness World Records–we checked).

movato bloggreen2

Surprisingly, these au naturel roofs have practical uses, in addition to the aesthetic benefits.

Grassy housetops can:

  • -Absorb rainwater overflow
  • -Reduce the cost of your utility bills (woohoo!) by absorbing sunlight in hotter months
  • -Better insulate your home against changing temperatures
  • -Act as a sound barrier, particularly in large cities (no more being woken up by drunken shouting at 3 a.m.)
  • -Counteract the urban heat island effect

Don’t grab your ladder and head up top just yet, though–you’ve still got a weight-bearing issue to ponder.

It’s Surprisingly Heavy Being Green

For those of you seriously considering this undertaking, a green roof requires four central components:

  • -Waterproof seal
  • -Roof-protection barrier
  • -Drainage system
  • -Soil

Keep in mind that adding all of these elements can make your roof’s life a little heavier.

IF your roof can hold the weight of a green roof, then installation will require little more than a trip to your local home improvement store.

But that’s a big if.

Think about it. Add a day’s worth of rainwater, and your roof is suddenly very, very heavy from soaked soil and runoff.

It’ll be just like a reenactment of that Allstate commercial where the “mayhem” dude falls through the roof. Except with dirt. And onto your face, not your car.

So it’s probably best to seek a professional’s advice about just how much weight your roof can support.

Once you figure out that minor detail, though, it’s on to the greens!

The Grass Is Always Greener On the Roof

We’re still lacking one key ingredient for our rooftop lawn–the grass.

To calculate just how much cow food our roof could grow, we needed a house size to work with. Since us novelty real estate bloggers are rather fond of averages, we stuck with our typical 2,500-square-foot American home.

Renovating your roof into a mini garden is hunky-dory as long as the pitch, or the angle of the roof, is 30 degrees or less–don’t worry, that’s not very steep at all (but if you’re afraid of heights, you might want to pay someone else to do the work). Knowing our home is a square and has a roof pitch of 17.75 degrees, we were able to calculate the top’s surface area.

Turns out we would need 2,625 square feet of sod.

Sod is sold in chunks one foot wide and as long as nine feet. With this in mind, we calculated that our grassy decor would take about 292 rolls of sod.

If you’re really lazy, you could solve any and all vegetation roof problems with green roof tiles from Toyota Roof Gardens (yes, the company is related to the Toyota known for its oddly shaped eco-cars).

But then you would miss out on the best part of having a green roof–the furry critters that will function as your maintenance crew.

Every Roof Garden Needs a Grazer

Possibly the only thing more exciting than turning your boring roof into a sweet patch of grass is getting a pet to keep all that vegetation trim so you don’t have to. (In actuality, a shallow green roof requires little maintenance because it won’t grow very tall–and no, it doesn’t need to be mowed.)

Everyone loves a good grass-eating goat, but frankly we’re afraid the extra weight would cause our roof to cave in.

movato blog green3 1
That leaves us with two size-appropriate grass-munching pets:

  • -Chickens
  • -Guinea Pigs

So exactly how many would we need to keep our faux lawn trim?

Movoto’s handy animal mower calculator suggests 105 guinea pigs or 70 chickens–if you want your lawn mowed in a day.

We don’t actually advise such a large quantity of pets in this case, since the goal is to keep the roof relatively trim, not for your pets to mow it every 24 hours.

Movato Real Estate Blog
This article was originally published on February 20, 2013 on Movato Real Estate's Blog.

Our resident Internet conqueror found a chicken can consume about 0.375 pounds of grass per day, while a guinea pig eats on average about 0.25 pounds of grass a day. Knowing one square foot is equivalent to .01 pounds, we pulled out our TI-30 calculator and got to work.

If you wanted your roof fully trimmed in a more reasonable period of a week, you would need:

  • -10 chickens
  • -15 guinea pigs

Of course, that also means now you’ll have to house those guinea pigs or chickens–and preferably not on the roof, unless you want it to cave in or the neighbors to call ASPCA. Sorry, but you’re own your own if that happens.

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