For the St. Paul Fire Department’s
newest station, at W. 7th St and Randolph, the folks at city hall decided to get serious about eco-friendly design. And the bossest feature of the place is its multilevel showpiece 2-level 8,000 square foot green roof. Here are some of the reasons other municipal buildings will be acting jealous of the new green firehouse:
1. It’s Watershed-FriendlyClean watersheds mean clear and healthy lakes and rivers, friendly to fish and swimmers alike. But everything that goes into the city stormwater drainage system ends up in the watersheds--so the less stormwater runoff a city creates, the more healthy its local watersheds are. Rain runs off concrete roofs, but when it hits green roofs, it gets absorbed by the soil and used by the plants. Rex Greenwald, the
Stock Roofing project executive for the fire station roof, points out that the green roof put in at the Target Center last year relieved the watershed of plenty of drainage duty--an estimated 1 million gallons a year.
2. It Keeps the Heat Off the City“A typical roof can be 150 to 170 degrees,” says Greenwald, “but the temp of a green roof hovers around the ambient temperature.” For the building itself, this means a naturally cooler interior--and therefore, conservation of energy. But if green roofs were the norm across the nation, the benefit would be even bigger, because they would counter the
urban heat effect. Cities run several degrees hotter than their surrounding countrysides due to their large expanses of concrete roofs and roads, and their lack of cooling flora. Green roofs make up the difference and eliminate the problem-causing concrete, saving energy on a macro level and making early July evenings more bearable for the entire citizenry.
3. It’s an Air-Filtering AerieGreen roofs filter particles which may
contain pollution from the air, an especially important task in bigger cities, where the air flow can be sluggish. And of course, the plants suck in carbon dioxide and purify the air.
4. Farming Firefighters!“We have one area of soil 12 inches deep,” says Greenwald, “so they’ll be able to grow vegetables.” No one wants to trivialize the serious commitment to environmentalism this project represents, but the image of brave firefighters gently tending to blossoming vegetables on the roof of their firehouse is super cute. A trivial observation, but how could we not make it? The garden will benefit from irrigation courtesy of the upper roof level’s cistern, which will collect and hold rain water until its needed.
5. It’s ExperimentalThe fire station’s greentop is also a laboratory, where competing ideas can be monitored. “It’s called a classroom roof,” says Greenwald, “with 12 different designs--retaining walls and isolated areas allow different soils and different plants. Then they can study it to see what works and what doesn’t.”