I had admired from afar the green roof shed I saw my neighbors, Melissa and Bruni, building by hand a couple of years ago. When DIY Del Ray came into being, I leapt at the chance to interview them. I met with Melissa and we admired the finished shed and talked about how she and Bruni designed and built it.
Melissa and Bruni wanted a green roof on their shed because “they’re adorable and effective for retaining stormwater runoff,” says Melissa.
A green roof is also known as a “living roof,” and, in addition to reducing stormwater run-off, the plants can create a habitat for wildlife, lower urban air temperatures, filter pollutants and carbon dioxide from the air, and insulate buildings from sound. The Alexandria Duncan Library is the first green roof in Alexandria, VA. It was sown in 2005 with a variety of sedum, the same landscaping you can see on the grounds.
Melissa and Bruni started by defining the needs for their green roof shed. They wanted a shed large enough for bikes and lumber from their various DIY projects. (They have a workshop in their basement for kitchen, basement, and other past and current home renovation projects – the subject of a future DIY Del Ray post.)
They finalized the shed design using The DIY Guide to Green and Living Roofs by Dusty Gedge and John Little, which Melissa found online from Living Roofs.
With help from Melissa’s carpenter sister in Texas (over the phone), they built the entire structure by hand. They followed the City of Alexandria code for the total volume and height of the structure. The City did not include the height of the plants in the required height of the shed. Therefore, since Melissa and Bruni planned to use grasses and wildflowers, they didn’t have make the roof any lower than the basic height requirement.
One of the biggest challenges was converting the metric units in the British DIY manual to American units. Melissa wasn’t overly confident in her math when it came to calculating the load bearing struts, so she added more – one two-by-four every foot. “The shed is probably sturdier than our house,” she says.
She added that the overbuilding begins below ground – with eight 4×4 posts, each sunk in 2 feet of concrete. On one of their frequent phone consultations, Melissa’s sister assured her that “the shed was not going to come down.”
They worked on it during weekends over the course of about nine months. “We had the basic building completed before the blizzards in 2010,” explains Melissa, “but the doors and window, final trim, and paint had to wait until the snow melted.”
When they were done building the structure, they added dirt from the yard and planted wildflowers. Now, Melissa says “they get better grass growing on the roof than they manage to grow in their yard.” Plus, they have a lovely view of the colorful shed and wildflower garden from their kitchen window.
- Roof: Marine plywood; rim made of pressure-treated 4x4s split diagonally from Smoot Lumber Co.
- Pond liner between layers of special landscaping fabric to protect from punctures and tears, held in place with plastic 1×4 trim.
- Recycled cedar siding from Rebuild Warehouse.
- Remaining lumber from Home Depot.
Melissa and Bruni estimate that the shed cost about $2,000. They say they probably could have done a shed of the same size for about $1,000, if they had scrapped the roof, the window, and the recycled cedar siding. The marine plywood was more than $100 a sheet, and the pond liner and materials were about $500.
Posted by Leslie