Kresge Foundation Headquarters

Challenge

Designers were tasked with creating a native landscape to manage stormwater, demonstrate the Kresge Foundation’s mission of sustainability, and work around the local weed ordinance that disallowed grass taller than three inches. It was also important to preserve the site’s rural character in a highly urbanized area; blending together historic farm houses with the sleek, energy-efficient headquarters was necessary. Due to the small site size, storage of materials for reuse onsite was limited.

Solution

Due to the enthusiasm and support from the city of Troy, design for the native landscape at Kresge was approved. Farm buildings on the property were relocated to maximize efficient circulation while keeping the structures highly visible from the road. The new office building was designed to be sunken into the ground, resulting in a building that successfully blends in with the scale of the historic buildings and creates a depression to capture and treat stormwater. Due to limited storage area during construction, recycled materials were often sourced from local suppliers rather than from the site itself.

• On-site stormwater management systems include constructed wetland ponds, bioswales, green roofs, and an 18,000-gallon stormwater cistern.
• The permeable parking lot infiltrates stormwater, recharging groundwater and reducing the flow of water into city sewers.
• Relocating the drive and parking lot reduced the amount of paved area, creating more space for plants and native landscape.
• Approximately 72% of the site is covered with native plants, reducing the need for irrigation. Turf grass area was reduced by 64,500 square feet (88%).
• The landscape showcases a variety of habitat types, including woodland, tall grass prairie, wet meadow, mixed prairie, shoreline, emergent, and open water areas. These have attracted a fox, great blue heron, a nesting pair of Canada geese, a muskrat, skunk, chipmunks and a sharp-shinned hawk.
• Replacing lawn with native plants has reduced the need for weekly mowing, with the exception of the city-owned easement. All other landscape maintenance is done by hand, eliminating air and noise pollution.
• Annual controlled burns are effective in controlling invasive species, encouraging the spread of native plant communities, and creating a functional ecosystem while providing educational opportunity for the community.
• Plant labels introduce visitors to Michigan’s native prairie plants and interpretive signs help to educate about native plant communities and stormwater management practices on the site.
• The agricultural character of the site was maintained by preserving and utilizing existing historic farm houses.
• Four green roof areas provide building insulation, absorb stormwater, blend into the surrounding landscape, and extend the life of the roof.
• Solar orientation of the building reduces summer cooling and winter heating costs while optimizing views onto the landscape. High-reflectance white roof areas minimize urban heat island effect.
• The LEED-platinum office building incorporates 27% recycled materials, with 76% of all construction materials sourced within 500 miles from the site, reducing transportation costs and emissions.
• Approximately 318 tons of locally-sourced crushed concrete was recycled to form the gabion walls, using higher-quality trap rock stone only as a facade.
• The Kresge Headquarters was designed to provide views to the landscape from all 52 employee desks. However, due to unanticipated staff increases, an additional 16 employees are working at new work stations, which do not direct views to the landscape.

• Native landscapes save $30,500 in irrigation and maintenance costs each year, when compared to maintaining the same area as a traditional perennial garden.

• Outreach and open communication can challenge a regulation and set new precedent. The city of Troy building code requires grass to be kept three inches or shorter. Thanks to the City’s enthusiasm and interest in the Kresge project, and open communication between the architects and city officials, the project was able to proceed with its plans for natural landscapes. This experience also promoted awareness of green practices within the local government.

• The decision to pursue LEED certification should be made as soon as possble in the process. Though the building doesn’t have to be LEED certified to be green, Kresge thought this documentation would lend credibility to the building as a model for other nonprofits. Because this decision was made early on, “LEED services” were included in the architect-engineer team’s scope of work.
• For sustainable projects, having firms and individuals with green experience on the design and construction teams greatly facilitates the process. For the design of this LEED building, a consulting architect that specialized in sustainable design was hired to augment the design expertise of the lead architect. Whenever possible contractors and subcontractors with green experience were hired. Throughout the entire process, standard practices were replaced with green alternatives.
• Establishing native plants from seed requires more irrigation than expected. Because many of the native prairie plants were seeded rather than planted as plugs, it took several growing seasons for them to germinate and take root. This required 3.5 years of irrigation.

• Because sustainable practices are not yet standard, open communication is needed to ensure that sustainable landscapes are properly managed. In the first year, the entire site was mowed rather than hand weeded as specified, setting back many of the newly planted plugs. This may have reduced the ability of native plants to outcompete annual weeds.
• Native landscapes require stewardship; traditional turf landscapes require maintenance. It is important to distinguish between these two practices, as the budget and time required for each is different. Traditional office landscapes of turf and trees are maintained to look the same for as long as possible. Native landscapes require management that doesn’t focus on maintaining a static state, but that changes with the plants and seasons. Projects that are considering native landscapes must also consider the time and expense required for appropriate management, which is typically greater than traditional turf maintenance.
• Scheduling prescribed burns in an urban area is difficult, even with municipal support. Kresge’s annual burn requires significant planning to schedule a time when the weather conditions are favorable, the local fire department is available, and the surrounding office park will be minimally impacted.

Project Team

Kresge Project Manager: Ron Gagnon
Architect: Valerio Dewalt Train Associates
Consulting Architect for Sustainability: Farr Associates
Mechanical, Electrical, Plumbing and Fire Protection Engineer: Arup
Structural Engineer: Robert Darvas Associates
Landscape Architect: Conservation Design Forum (now Environmental Consulting & Technology, Inc.)
Civil Engineer: Progressive AE
Farmhouse Interior Designer: Interiors Group Searl Blossfeld
Lighting Designer: Lighting Design Alliance
Acoustic and Vibration Engineer: Shiner + Associates
Preservation Consultants: Vinci-Hamp Architects
General Contractor: JM Olson
Landscape Contractor: WH Canon

Role of the Landscape Architect

CDF served as the project landscape architect and participated in an integrated design process with the project team. CDF was responsible for sustainable site/landscape design, specification, bid review, and construction oversight, which included the design and sizing of the site rainwater systems, including rainwater harvesting/ re-use, created wetlands and bioretention.