All Posts Tagged With: "Emory Knolls Farms"

4 Myths and 1 Important Truth About Greenroofs

photo: courtesy Furbish Company

I’m consulting on a community poolhouse project and the design team is considering a 6,000 square-foot greenroof. The building committee has gotten nervous about this kookie technology: is this decision going to be cursed by future generations? Turns out, there are at least 10 acres of greenroofs in the D.C. area alone. People have figured them out and are installing greenroofs to slow down and filter stormwater, provide a cooling effect and supply a green habitat, among many other benefits . I spoke with two leading experts in our area: John Shepley from Emory Knoll Farms and Rick Truett from Furbish Company . Here are the myths and their answers:

Myth #1. They are expensive and need specialized maintenance.

Yes, they are expensive; they can run roughly double the cost — or more — of a conventional commercial roof. But they also protect the roof’s membrane from the damaging effects of the sun’s UV rays , wind, and extremes of temperature fluctuations. This can double the life of the membrane — or more. Rockefeller Center in NYC has greenroofs from the 1930s that are still on the original membranes. Another important consideration on cost results from systems thinking . That is, for sites that have challenges handling rainwater (aka, stormwater) in conventional ways, greenroofs are a godsend. (See Myth #4 below for more on this.)

Upkeep is minimal. A 10,000 SF mature roof would require 1 to 2 person-days per year, maximum. For the first two years, there would be a bit more maintenance to get it to maturity, but not that much more. On a little roof of less than 2,000 SF, the initial work would be would be 3 days the 1st and 2nd years, then a half-day or less every year after that.

Myth #2. In Europe where they are more common, greenroofs are on buildings with trained, equipped, full-time maintenance staffs. They have to rake leaves in the fall, remove pollen-related detritus in the spring, pick up dead branches throughout the year, reseed or replant bare spots, and fertilize wearing safety harnesses when near the roof’s edge.

I have done tiny, 300 square-foot additions with greenroofs. Continued

Green Roof Plants

arranged by: alyssa

Green Roof Plants is located at Emory Knoll Farms in Street, Maryland. Proving over 100 varieties of plants Emory Knoll has extensive experience with roofing systems, soil mixes, climates, and working with manufacturers and designers. The farm also supports sustainable design by having solar pumps for all water needs in the greenhouse and photovoltaic panels for most electric needs.