Green Roofs
By: Kira Miner
Updated: March 31, 2009
>Most development projects include a budget for landscaping.
Plants usually line a building's facade, or maybe a few trees, but now, developers are starting to look up.
From the parking lot of this shopping center, you can see something a little different.
It's literally a green roof. It's made of several layers.
The base is a traditional roof, and on top is a layer of drainage, a root barrier, soil, and finally the plants.
Those plants absorb a lot of rainwater, but not all.
The runoff is collected in a cistern and is used to flush the building's toilets.
"Now we're using 70% less city water, so we have a 70% lower sewer bill."
And then you have the whole insulating value of this whole upper roof area.
That means the heating and cooling systems don't run as much.
There's an even bigger effect on the community.
The roof isn't made of dark materials that absorb sunlight throughout the day and then release that heat at night.
The cumulative effect of that throughout the city is you have a really hot night sky and it actually changes weather patterns.
It did cost more to buy the green roof materials, but the installation was "dirt cheap."
Volunteers provided the labor.
Grants and tax credits also helped.
Combine that with energy savings, and it's starting to pay for itself.
O'Reilly also says you can't put a price on publicity that gets customers in the door, and the customers seem to like what they see.
"It's delightful. There are actual natural things up here to look at, and it feels good."
It is slightly more expensive to do a green building but there's always a measurable cost benefit, with regards to the health of the people inside, or the efficiency of the space, or the lifecycle costs of the building. It always pays off.
