Dansko Strides toward
3 Green Roofs
A LEED GOLD CERTIFICATION FOR DANSKO’S
CHESTER COUNTY, PA, headquarters brought founders
Peter Kjellerup and Mandy Cabot a step closer to their green
goals. The 90,000-square-foot facility features three vegetated
roofs, one of which houses a patio with a pergola and is accessible
to employees (top left). The entire east wing is covered by the largest of the three.
The environmental benefits are a popular motivator for would-be green roof owners, along with stormwater management and
aesthetics, explains Brian Lambert, Director of Products and
Systems for the Garland Company, the roofing manufacturer that
supplied modified bitumen for the project’s green roofs and other
A triple installation crowns the footwear company’s headquarters
flat areas and metal roofing for the steep slopes.
The headquarters building also incorporates a store for Dansko
footwear. The green roof over the retail area features plants and
shrubs and is visible from the clerestory windows (bottom left).
The roof is a mix of semi-intensive and extensive installations
incorporating cuttings and plugs (starter plants raised in individual cells to prepare them for planting). The plants are sedums
and succulents. Plant choice is dictated by the local climate and
the amount of growing media the roof can hold, explains Lambert.
“Some plants can grow in 2 to 3 inches of media, like a sedum or
a low-growing ground cover,” Lambert says. “More elaborate types
of plants may need a deeper soil mix, which is going to increase the
weight load. These are things you need to think about early on.”
This project was a new build, so the team had the opportu-
nity to get the waterproofing (a vital component of any roofing
project) right from the start. A green roof retrofit for an existing
building should be paired with a new waterproofing system,
“A green roof is not a roof to cut corners on. The waterproofing
portion has to be detailed, designed and installed at a high level
because once the greenery is in place, it’s more difficult to find a
leak. That sounds basic, but it’s often forgotten,” Lambert explains.
“A lot of people get wrapped up in the vegetation or aesthetics and
forget about making sure it’s watertight. If the plants are beautiful
Increased insulation to reduce cooling costs, rainwater
management and material conservation by extending
the life of the roof.
Three green roofs covering about 30% of the 90,000-square-