Barn Series: Green Roofs
One of our favorite aspects of our container barn is something you may not even notice if you don’t know where to look. On the three exposed roofs of the shipping containers, you’ll find a miniature meadow. These green roofs are packed with a mixture of perennials and grasses, plants that are drought-resistant and require minimal maintenance. Standing in our courtyard, the plumes of green are just barely visible over the container’s edge.
These plant installations aren’t just ornamental. Like so many aspects of our farm, they serve multiple purposes and demonstrate an important solution for major climate change-related threats to urban environments, like stormwater management and heat stress reduction.
Our green roofs were installed by Living Roofs, Inc., based out of Asheville, North Carolina. We caught up with co-founder Kate Ancaya to discuss the role of green roofs in urban planning and design, and how they can help address the climate challenges we face.
Tell us about the design of the Burkett Farm green roofs. What plants are part of the installation? Was there anything unique or unusual about the construction based on the shipping containers?
We designed the green roof system to support a mix of perennials and grasses, creating meadows on the shipping containers. We were excited to install an unexpected planting area on the shipping containers, softening their industrial look. Though the roofs are small, we were able to pack in a mix of perennials and grasses to support pollinators, maximize the stormwater benefit, and “peek” over the edge so the plants are visible from the ground. We used different plant layers (groundcover, mid-height, and seasonal) to maximize plant coverage, suppress weeds, and keep the growing media moist. Plants include Allium schoenoprasum, Amsonia ‘Blue Ice’, Carex stricta, Sporobolus heterolepis, Phedimus takesimensis, Petrorhagia saxifraga, and Talinum calycinum.
What inspired you to focus on green roof design?
Living Roofs, Inc. (LRI) was founded in 2006 and was the first company in North Carolina dedicated to vegetated roofs and landscape on structure projects. Emilio and I created the company to explore the potential of green roofs as a way to bring nature into cities and increase resilience in the Southeast region. We envision green roofs as natural infrastructure unfurling across the built environment, weaving nature back into the urban fabric. Over the years, we've tested new systems, experimented with entirely new approaches to planting green roofs in the region, and grown LRI into a company with an impactful regional reach.
What are some of the most innovative or challenging green roof projects Living Roofs has undertaken?
Green roofs were not widely known in the Southeastern region when Living Roofs, Inc. began in 2006. At that time, green roofs used a European model and system build-up that suited northern climates, with very shallow growing media depth and predominantly planted with Sedum species. But in our climate, these aren't always a great fit—only a few Sedum species flourish on green roofs in the Southeast due to our humidity and extreme heat.
Over the years, LRI developed techniques to build green roofs with greater plant diversity, better stormwater management, and more overall resilience. Through inspired experimentation, we've identified plants well-suited for living roofs in the varied environmental conditions of the Southeast. In 2016, we made a dramatic shift in how we approached plant selection and design in order to enhance biodiversity, create multi-species habitats, restore native plant communities, and provide stopover habitat for migratory species.
Installation in process.
One year later.
“Heat stress is a significant public health concern, especially in the Southeast. Research shows that vegetated roofs help cool cities by reducing temperatures, which also leads to decreased energy costs. The EPA cites that green roof temperatures can be 30–40°F lower than conventional roofs and can reduce city-wide ambient temperatures by up to 5°F. ”
What are the environmental benefits of the type of green roofs you install?
Well-designed, high-performance green roofs act as nature-based infrastructure and are a tool for building regional resilience and meeting the challenges of climate change. Vegetated roofs turn barren, overlooked areas into living stormwater infrastructure that provides a cascade of community-wide social and environmental benefits. Green roofs address climate challenges impacting our region by reducing rooftop temperatures to combat urban heat island effect and diminished air quality, improving water quality by filtering and significantly reducing stormwater runoff and peak flow, and amplifying plant and invertebrate biodiversity. For these reasons, we reframe green roofs from merely a visual amenity to multi-purpose infrastructure that provides critical ecosystem services.
Heat stress is a significant public health concern, especially in the Southeast. Research shows that vegetated roofs help cool cities by reducing temperatures, which also leads to decreased energy costs. The EPA cites that green roof temperatures can be 30–40°F lower than conventional roofs and can reduce city-wide ambient temperatures by up to 5°F.
Vegetated roofs are the first line of stormwater capture in urban areas and play a vital role in reducing storm runoff that surges onto our streets, flooding communities and eroding our creeks, streams, and rivers. In urban areas where stormwater infiltration is infeasible, vegetated roofs can perform valuable water management functions by retaining rainfall, detaining runoff, and increasing evapotranspiration. NC DEQ recognizes green roofs as a Primary Stormwater Control Measure, which means they can be designed to satisfy stormwater requirements in conjunction with, or in place of, single-purpose grey infrastructure.
How does Living Roofs measure the success and impact of its green roof installations?
Stormwater is one of the main issues driving the inclusion of green roofs on our larger commercial projects currently. As nature-based infrastructure becomes an accepted way to meet municipal requirements for stormwater management, it solves a developer’s problem while providing a cascade of other environmental benefits. We work with a stormwater engineer to measure the effectiveness of our installations at managing stormwater volume and flow rate.
We endeavor to include a diversity of native species in our planting plans. Although we haven’t studied our roofs’ effects on biodiversity in a concerted way, we see lots of beautiful pollinator species, bird nests, and abundant invertebrates on the roofs we maintain.
What role do green roofs play in the future of sustainable architecture and urban planning, and how do you envision Living Roofs contributing to that future?
The infrastructure of the future is resilient and multifunctional! We believe green roofs and nature-based infrastructure are vital components of sustainable architecture and urban planning. With these tools, we can build regional resilience through impactful design, bring beauty and life to often overlooked spaces, and employ nature-based solutions to problems in the built environment. We envision Living Roofs, Inc. helping to shift the perception of green roofs from mere optional ornamentation to a standard practice by designing, building, and maintaining high-functioning landscapes on structures, and through education and advocacy.