Luxury Goes Green

In Greensboro, North Carolina, designers of the Proximity Hotel show that upscale lodging can be sustainable too.

By Jayne England Byrne

Certified LEED Platinum, the hotel reflects Greensboro’s past as a thriving textile center. Credit Mark File

Upon arriving at the Proximity Hotel, it immediately became obvious I was visiting a luxury property. A door attendant greeted me at the revolving door. The lobbies, filled with abundant natural light, boast a sophisticated blend of hard and soft surfaces. Silky fabric hangings and plump toss pillows complement concrete columns, a pair of locally crafted steel spiral staircases, and a cantilevered reception desk. And fine dining awaits in the hotel’s restaurant, the Print Works Bistro.

But the Proximity Hotel’s prestige isn’t limited to the upscale, elegant experience it provides for its guests. A visit here is also a grand experience for engineers interested in sustainability and green building practices. Located in suburban Greensboro, North Carolina, the eight-story, 147-room hotel was the first hotel in the United States certified LEED Platinum by the U.S. Green Building Council. Opened in October 2007, the Proximity received its Platinum certification for New Construction in October 2008.

Developed as a third-party verification system, LEED (Leadership in Energy and Environmental Design) uses a point system to quantify a building’s sustainable practices. It evaluates both the design and operation of a building, with points awarded across broad categories of sustainability. Examples of new construction prerequisites for certification include “Construction Activity Pollution Prevention” and “Storage and Collection of Recyclables.”

In addition to satisfying the prerequisites, a project can accumulate credits for sustainability practices. Projects earn credits for practices such as “Light Pollution Reduction” and “Innovation in Design.” The level of certification depends on the total number of points earned, with Platinum ranking as the highest.

A Legacy Hotel
Dennis Quaintance, CEO of Quaintance-Weaver Restaurants & Hotels, did not set out to build a LEED Platinum hotel. But he did start with a long-term vision. Jeff Kennedy, general manager, explained that Quaintance had envisioned the hotel as a legacy project, a hotel that would have a lasting, positive impact on the community. Kennedy explains, “We are very conscious of our stewardship, both locally and globally.” Those core values include providing a luxurious guest experience while acting in a socially and environmentally responsible manner. Centrepoint Architecture of Raleigh, NC designed the building, while Superior Mechanical of Randleman, NC handled mechanical engineering and contracting.

As one of many sustainability features, a green roof is taking root.
Credit Jayne England Byrne

The Proximity’s design echoes a 1930s cut-and-sew factory, a style that pays homage to Greensboro’s textile mill heritage. In the past, much of Greensboro’s growth came from its vibrant textile industry. The hotel is named after the Proximity Cotton Mill built in Greensboro in 1895. The restaurant, the Print Works Bistro, gets its name from Proximity Print Works, a Greensboro cloth printing plant that opened in the early 1900s.

Kennedy started working for Quaintance-Weaver in 2005. While his educational background is in religious studies, he learned much about the construction industry while growing up, and he is licensed as a North Carolina General Contractor. When Kennedy began working for Quaintance, he had recently returned from teaching at a missionary school in Vienna, Austria. Kennedy’s time in Vienna had shifted his priorities. “The experience led me to develop a global mindset and a heightened awareness of good sustainability practices,” he says. Living in Vienna, he came to rely on public transportation and smaller living quarters, and he “learned a lot about environmentally friendly building.”

Upon returning to Greensboro, Kennedy discovered that the opportunity to work on the Proximity was a perfect fit for his new mindset. Kennedy participated in weekly design team meetings and weekly construction meetings. He described the decision process as a series of multiple lenses. LEED became the “roadmap to overlay on top of our values,” as he puts it. But every decision was also filtered through the lens of the guest experience. Ultimately, only solutions that did not compromise the guest experience made it into the final design.

Tony Villier, service manager at the Proximity, took me on a Sustainability Tour. He also described LEED as a component of the Proximity’s design process. LEED was seen as a widely accepted, independently verifiable framework that could be used “to ask good questions.” As a matter of course, the design and build of a hotel will consider cost and guest experience. This design team added another question to each decision: Is there a more sustainable way to do this?

Sustainability Tour
During the first year of operation, 9000 visitors took the Sustainability Tour, an in-depth, behind-the-scenes look at the elements that helped the Proximity achieve Platinum status. The tour remains popular. In fact, Villier noted that 20 percent of group sales are attributable to the hotel’s LEED status.

An engineering professor at nearby North Carolina A&T State University, Peter Rojeski and his students have assisted with measuring and verifying energy use data.

The first stop on the tour was the Weaver Room. It was late Saturday afternoon, and the staff was busy preparing for an evening wedding reception. Sunlight streamed in through the large, low-e glass windows. Natural light is a design feature throughout the property, as over 97 percent of normally occupied spaces are day-lit. The Weaver Room overlooks the restaurant’s rooftop, and the view includes the beginnings of a vegetative roof. Villier explained that they are experimenting with various plants, aiming to find plants that can thrive without watering or soil enrichment. An effective vegetative roof can help with stormwater runoff as well as save energy.

A terrace provides a view of a refurbished stream. An area that was once a stagnant drainage ditch now qualifies as a North Carolina state conservation easement. Boulders and logs provide grade control, and native and adaptable plants complete the landscape.
The next stop was the kitchen area of the Print Works Bistro, an elegant restaurant with a seasonal menu that emphasizes local food sources. The ventilation hoods have variable-speed fans that typically operate at 25 percent of full capacity. Sensors detect heat and smoke, and fan speeds adjust to accommodate the load. The restaurant’s refrigeration equipment uses a closed-loop geothermal system.

From the restaurant, we took an outdoor passageway over to the Social Lobby. On the way, Villier pointed out that the property’s landscaping does not include any turf grass. To reduce water consumption, only native or adaptive plants are used. A drip irrigation system directly waters the plants’ roots and uses less water than a conventional sprinkler system.

On our way to the lobby, we took a quick look in the men’s restroom. Why did I need to go in there? It was my chance to see the waterless urinals, 1.1 gallon/flush toilets, and 0.75 gallon/minute faucets!

Jeff Kennedy had described the Proximity as Dennis Quaintance’s vision “realized in concrete, steel, glass and fabric.” Nowhere is this more evident than in the Social Lobby. While I was admiring the beauty of the space, Villier was pointing out the recycled content statistics: 20 percent overall, 90 percent in the structural steel and 100 percent in the gypsum wallboard.

Piping and pumps for two of the four solar arrays, which supply hot water. Credit Peter Rojeski

We took the elevator up to the guest rooms. The elevators are the regenerative-drive version of the Otis Gen2 model. In contrast with a traditional elevator system, this elevator only uses energy while going up. Villier estimates that the elevator system uses 50 to 70 percent less energy than a traditional system.

Ten-foot ceilings are the norm in the spacious guest rooms, and so is a fresh air circulation rate of 60 cubic feet/minute. In touring the guest rooms, Villier pointed out that “guest bathrooms are a make-or-break area” for a hotel. Testing was an important part of the selection process for the water-efficient toilets, showerheads, and faucets. Throughout the tour, Villier stressed that “efficiency can’t override the guest’s experience.” Not only would that be bad for business, it would also “hurt the sustainable building movement.”

The roof was our last stop on the tour. A 4000-square-foot solar thermal system supplies approximately 60 percent of the property’s hot water. Designed by FLS Energy in Asheville, NC, the closed-loop system uses a glycol solution as a heat transfer fluid. Four water storage tanks hold about 1500 gallons each.

Known as “the Penthouse,” the rooftop equipment room includes two boilers. During stretches of summer heat, there is no need for a boiler, as the solar energy system supplies all the hot water. Even in the winter, one boiler would be sufficient; second one is redundant.

I later spoke with Dale Freudenberger, president of FLS Energy. He described the slope of the solar panels as an interesting design challenge. Quaintance originally proposed a 10-degree slope to suit the aesthetics of the building, whereas Freudenberger thought the ideal angle for the system would be 40 to 45 degrees. In the end, FLS Energy was able to make the system work with a 19-degree slope. Freudenberger called the project a launching point for his company. “It was our first large, commercial project and a great experience.” FLS Energy continues to improve and troubleshoot its system. I found this type of subcontractor relationship typical with Quaintance-Weaver. By having subcontractors participate across multiple phases, minimal disconnects between designers and operators occur.

Measurement and Verification
The Proximity continues to improve its energy efficiency with a measurement and verification (M&V) program. The M&V program compares actual energy use to the projected use, and the method requires data collection at the subsystem level. Initially, the property was not set up for this type of data collection. It only had a single gas meter and a single electric meter, and those meters served both the hotel and restaurant.

The hotel’s lobby. Credit Mark File

Dr. Peter Rojeski, a professor in the Architectural Engineering Department of North Carolina Agricultural and Technical State University (A&T), has been an integral part of the M&V program. Once extensive submetering equipment was installed, Rojeski and his students began collecting and analyzing data. Through a cooperative arrangement with the university’s Center for Energy Research and Technology (CERT), the Proximity benefited from free consulting services, and the students had an opportunity to use a luxury hotel as a laboratory. Monitoring equipment includes electrical current submeters, an outdoor weather station, and a BTU meter for the solar subsystem.

Adams Environmental Systems of Kings Park, New York began working on the M&V program in September 2008. The company designed and installed sensors to monitor the air temperature, humidity, and carbon dioxide levels of the indoor air. It also maintains the data acquisition system that monitors electricity consumption, gas consumption, HVAC parameters, and the domestic hot water supply. A multiple-channel data logger has remote monitoring capability.

David Adams, president of Adams Environmental Systems, described the Proximity project as “a new endeavor for our company and certainly an adventure.” Before the Proximity, their core business had been building weather-monitoring systems. With the Proximity, what began as “a relatively simple monitoring system has blossomed into a full-blown LEED M&V system that can remain in place at the hotel and constantly monitor the efficiency of its systems.” He now considers M&V monitoring systems another part of his company’s core business.

The results of M&V lead to operation tuneups. For example, the solar system has increased its BTU output by 20 percent since beginning operation. FLS Energy changed the flow characteristics to better balance the flow through the entire system. The air vents have been changed to a type that functions better at higher temperatures, and the heat exchangers were replaced with higher-capacity versions.

Rojeski and Adams have been working on a real-time energy consumption display for guests and visitors. In addition to meters, the graphics translate energy savings to an easily understandable, steadily updated format. The information will be viewable from the guest room televisions, and a lobby hallway will have an educational kiosk with a similar display for tour groups.

An ongoing M&V program enables the Proximity to continue to improve its energy performance, but that is not the only forward focus of the hotel’s management team. They are also moving toward a paperless operating system and continue to look for ways to incorporate more local produce. Meanwhile, the Quaintance-Weaver company’s other hotel in Greensboro, the O. Henry, is getting attention as it prepares for a LEED for Existing Buildings Certification.

Jeff Kennedy described the Proximity as a “designer’s hotel,” and I agree. From the lobby’s industry-meets-glamour interior design to the energy-efficient equipment in the Penthouse, the Proximity serves as a showcase of good design principles.

A freelance writer in Greensboro, NC, Jayne England Byrne serves as the vice-chairperson for ASME’s Carolina Section.

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