Greening goes Gold at Warren Wilson with LEED certification of Orr Cottage

Orr Cottage

Warren Wilson College has become the first college or university in North Carolina to have a Gold Certified Building under the Leadership in Energy and Environmental Design (LEED) rating system, developed by the U.S. Green Building Council. The college received the distinction for its recently dedicated Doug and Darcy Orr Cottage, which houses the offices of Admission and College Relations.

Nationwide, fewer than 150 buildings of any type – including about a dozen on college campuses – have achieved the Gold LEED designation. In North Carolina, the only other building so designated is Third Creek Elementary School in Statesville.

The Green Building Council seeks to promote the construction of buildings that are environmentally responsible, economically profitable and healthy places to live and work. In order to achieve a Gold LEED certification, buildings must meet a prescribed number of standards under the categories of site sustainability, water efficiency, energy and atmosphere, materials and resources, indoor environmental quality and innovation.

Orr Cottage is an arts and crafts-style building that was constructed using stone from nearby mountains and wood siding and trim milled from the college forests. A recent Warren Wilson College graduate, Biagio Scibetta, was project manager for the in-house project that was completed with the extensive involvement of a dozen student work crews. The structure blends “the poetic with the practical,” in the words of building architect Steve Farrell.

Paul Braese, director of the college’s Facilities Management and Technical Services, praised LEED for driving that practicality.

“Efficiency has more to do with operations than with conserving, which leans heavily on human behavior,” he said. “Conservation won’t do well in the real world if people won’t buy it.

“LEED has helped by instituting standards and systems that set comfort alongside sustainability. We have built a structure that is beautiful and livable, and will use 50 percent less energy than a conventional building of the same size.”

Braese hopes Orr Cottage will help showcase the marriage of green building and fiscal responsibility.

“The Green Building Council has gathered together people who are becoming the gears of the system,” he said. “The ones saying, ‘We can do this – this isn’t more expensive; it’s smart.’

“The [green] movement is growing exponentially. I see it when the state of North Carolina has its first energy conference ever, for sharing information and measuring the performance of institutions. I see it when individuals, contractors and managers seek LEED certification. People are seeing connections, possibilities.”

DOUG AND DARCY ORR COTTAGE
Green Building Highlights

Outside
§ The site is reused, built on ground where the Early Learning Center (relocated) formerly stood. In addition, to offset the construction and development, the school has pledged not to build on an adjacent green space equal to the development footprint for the life of the building. The orientation of the building takes advantage of soft east light and minimizes harsh west light. It also takes advantage of sweeping views of the Swannanoa River Valley that include 300 acres of college farm fields, 600 acres of college forests and the verdant mountains beyond.

§ A bio-retention trench collects and filters stormwater on-site. Another water-collection feature is the installation of non-clogging French drains.

§ The tight building envelope includes elements such as a radiant barrier, spray-foam insulation (Icynene), and a ground-source heat pump that allow the building to operate with half the energy of a conventional structure of the same size. “California Corners” were installed in the exterior wall corners to accommodate insulation. Tee posts were installed where interior walls intersected with the exterior walls, allowing for more insulation to be blown in behind walls. Insulation strips were installed over all exterior walls to create a thermal break between the studs and the sheetrock.

§ Light pollution reduction is effected by outdoor low-level lighting that does not light up the sky. The lighting design also prevents interior lights from projecting out windows, thus ensuring that this essential element of nocturnal wildlife remains undisturbed.

§ The use of local or regional materials includes all of the wood siding, which comes from Warren Wilson forests, sustainably harvested and milled by the Natural Resources Crew. The tree timber columns that support the front portico are also from the college forests. The boulder wall, steps, and terrace are all native stone, with much of the masonry performed by a college alumnus. Other materials from local-regional sources include the heat pump loop pipe, concrete, gravel, drywall, shingles, upper level front door, foundation drain material, insulation, stucco, floor and roof trusses.

§ Exterior paint contains “Insuladd,” a ceramic powder that lengthens the life of the paint.

§ The windows – casement, double-paned, and low-e for low air-infiltration – are also larger to allow more natural light into the building. Exterior shading is being installed over the lower level windows.

§ Native landscaping, a “given” at Warren Wilson but not required by LEED, will include drought-resistant plants as a water-saving device.

§ Approximately 90 percent (25+ tons) of construction waste was diverted from the landfill. All construction waste was monitored.

Inside

§ Daylighting is a design emphasis, resulting in 90 percent of the interior areas receiving daylight and views of the campus. Both the upper and lower levels use antique, recycled doors with glass panes that allow light to penetrate from the exterior offices to the interior space. A light shelf, to allow for further light penetration into the building, was also installed in the lower level exterior offices.

§ All lighting is energy-efficient compact fluorescent – electronic ballasts and T-8 lamps. To simulate natural daylight and minimize light levels, 5000 degree Kelvin lamps are being used. The majority of the light fixtures are indirect cove lights, or 80 percent indirect/20 percent direct fixtures to provide the best quality lighting. Motion detectors were installed for all conference rooms, bathrooms, and storage rooms for automatic shutoff when those spaces are not in use.

§ All interior paints, clear-coats, glues, and carpeting are low-VOC. Additional attention was paid to indoor air quality (IAQ) during construction by covering duct openings to prevent dust and dirt from collecting inside. This also protected the entire system prior to start-up.

§ Water use reduction exceeds the 1992 Energy Policy (which dictates amounts of water flow for certain types of fixtures) by 30 percent, by using dual flush toilets and low-flow, motion-activated bathroom faucets.

§ Energy efficiency, in addition to the building envelope mentioned above, include the forced-air geothermal heat pump that circulates water 400 feet below, where the earth’s temperature is a constant 55 degrees. The water moves through mechanical systems to heat or cool the building as needed and creates a cost-cutting system that is 70 to 80 percent more efficient than minimum code requirements.

An energy recovery ventilato
r is used to provide fresh outside air.

§ Wind power credits purchased from a Green-e certified vendor will offset 100 percent of the building’s energy usage for the first two years of its occupancy.

§ Monitoring equipment reveals how well energy systems are working.

The controls are fully digital, and the lighting, equipment, and outlet loads are all independently monitored for consumption. The wall envelope is thermally monitored to determine the wall temperatures outside the radiant barrier, and at various locations within the insulation. Carbon dioxide is also monitored.

§ Use of rapidly renewable materials includes formaldehyde-free wheatboard, from which all interior cabinets, lower level desks, and shelving are built. Wheat is a rapidly renewable resource (harvested within 10 years) and is cost-comparable to plywood.

§ Use of local materials: the wainscoting and window trim consists of hard and soft woods harvested from college forests. Some of the wood was salvaged from local trees felled by a cyclical pine bark beetle infestation. Also from local/regional sources are the carpet tiles and hardwood flooring.

§ Waste reduction: Floor to ceiling heights were utilized that minimized wood waste.

§ Recycled materials include floor tile (consisting of high-volume recycled products), 80 antique interior doors, upper level desks and other furniture either reused or purchased from vendors specializing in refurbishing used furniture.

§ Green housekeeping involves the use of only those cleaning chemicals that are Green Seal-approved.