b2b_greenroof.html

<h1>Green Roof - Denny Middle School</h1>
<p>Denny Middle School has a large green roof that was originally designed in 2006 by Bassetti Architects (link to project case study) to slow down the rain from major storm events, capture carbon dioxide from the air, and support both photosynthesis and evapotranspiration. These features function together to reduce the impacts of stormwater runoff on the rest of the school campus.</p>
<p>Most roof tops just capture rain in gutters, drop it through downspouts, and pipe it to the nearest stream, in this case, directly into Longfellow Creek (link to Longfellow Creek Watershed drainage transparent layer with bright blue prominent line for the creek pathway) which flows north just behind the Denny school campus.  If there is pollution in the air or in the materials in the roof top itself, then this pollution is washed into the creek along with the stormwater.</p>
<p>The green roof on Denny Middle School covers 4,300 square feet(?) By engineering this green infrastructure solution into the architectural design choices of the building, Denny was able to reduce its stormwater fee (embed link to pdfs or website) to the city of Seattle by $3,000(?).<br>
Immediately after construction, green roofs need to be monitored regularly to ensure that the vegetation thrives. During the first season, green roofs may need to be watered periodically if there is not sufficient precipitation. After the first season, green roofs may only need to be inspected and lightly fertilized about once per year. The roofs may need occasional weeding and may require some watering during exceptionally dry periods. Green roofs need to be maintained as any other landscaped area. This can involve gardening and irrigation, in addition to other roof maintenance.</p>
<h3>Virtual WebCam Tour for Student Learning</h3>
<p>To study the engineering design choices that Bassetti Architects (link to project case study) used to construct the green roof on Denny Middle School, the collaborative 6th grade teaching team, (link to photo of teaching team) including the Spanish Dual Language Program, has developed a problem-based curriculum integrated across grade levels, to meet education standards while reducing the impacts of polluted stormwater runoff at their schools. Once a year, students follow their science teachers via webcam up onto the roof for a live interactive tour the green roof engineering system. Students study diagrams of effective green roofs assess the value in reduced stormwater fees, and make annual maintenance recommendations to the school district to ensure that the green roof is functioning as originally designed.</p>
<p>The goal is help students apply their knowledge of the engineering design process in the real world, in this case, on a fascinating green stormwater infrastructure feature on their own school roof top.</p>
<h3>Multiple Benefits of Green Roofs</h3>
<p>Green roofs can absorb and store approximately 50% of typical storm events.  Due to evapotranspiration and plant uptake, this storage is assumed to recharge once every four days.</p>
<p>Green roofs help cool the neighborhood by reducing the heat island effect. That’s when all of the cement in a city absorbs heat from the sun and radiates it back. Plants help mitigate the heat island effect by holding and releasing moisture, cooling the air.</p>
<p>Green roofs help insulate the inside of the building, too. You stay cooler in the summer and warmer in the winter. And you save money, because you don’t have to spend as much on your energy bill for heating and cooling systems.</p>
<p>Green roofs take in carbon dioxide from the air and process it through photosynthesis, releasing fresh oxygen that we need to breath, so green roofs help soften the impacts of climate change.</p>
<p>Green roofs can even attract a greater biodiversity of insects, birds and pollinating bees.</p>
<h3>Here’s How to Build a Green Roof</h3>
<p>At the bottom is the roof deck.  Add some waterproofing material. Then lay down a root barrier, followed by a sheet of moisture retention geotextile. Then add a rigid drainage mat. Next comes some filter fabric, and finally, just the right kind of specialized soil mix and… the plants.</p>
<p>The plants selected for a successful green roof need to be extremely hardy to withstand hot, direct sun and pouring rain with fairly shallow root systems.</p>
<p>Learn more about the top ten plant species for green roofs: <a href="http://inhabitat.com/top-10-plants-for-a-living-roof/">http://inhabitat.com/top-10-plants-for-a-living-roof/</a></p>