“The 600 tons from the geothermal field is supplemented with a 200-ton closed circuit fluid cooler, which was incorporated into the overall system design when taking the peak demands of all four end-users into account,” says Roush. “Each of the tenants has a water-to-water heat exchanger that enables them to use the loop water on one side while keeping their individual systems separated. That way, if they wanted to create chilled water or put equipment on the roof and use glycol, these elements can't ultimately end up in the main loop water.”

Units with vertical stacking can share cooling towers, plumbing runs, and electrical conduits. This means that construction sequencing, materials, and installation can be streamlined. The maintenance of these plug-and-play units is provided by removing the one unit and replacing it with another, allowing for virtually no “down time” to operations of the heating and cooling units.

Using this system that saved electricity and conserved water in the renovation of this existing building helped the architects meet their sustainable design goals.

Plug-and-Play HVAC: Historic Palomar Hotel Renovation

The renovation of the historic 1929 Art Deco hotel in Philadelphia, Pennsylvania, was part of the Kimpton's hotel chain's commitment to preserving the past within the environmental framework of Kimpton's EarthCare program. “We built a system that would be economically and energy efficient, while also allowing for maximum guest comfort,” says Todd Sorbo, principal at Exp, the consulting engineering firm for this project. “Kimpton has always valued efficiencies and quality so we determined that a heat pump system would be the best solution.”

Encompassing all guest rooms, meeting and commercial spaces, common areas, and the Hotel Palomar's restaurant, a new 210-ton mechanical system design incorporated more than 300 heat pump units, including 293 horizontal units and eight vertically stacked units. The units were ideal for the guest rooms in which individual and quiet control of the heating and cooling system was important. In the LEED® rating systems Credit EQc6.2 Controllability Of Systems - Thermal Comfort is an important aspect of the design for sustainable environmental quality in new construction.

“Retrofitting a historic building into a modern hotel has its challenges,” says Jim Kohler, project manager with Tracey Mechanical, the project's mechanical contractor. “But the new heat pump system that we put into place was a good fit for the needs of the hotel, especially in regard to improving energy efficiency while needing to work within the constraints of an existing and historically protected infrastructure.” These units could be stacked one above the other and many placed in the ceiling to save space and maintain the integrity of the historic building. Each guest room was equipped with a smart digital thermostat that communicated to a central control board that sensed occupancy, Kohler says. “That way, if a room remains unoccupied for so many hours, it would shut off the pumps in order to reduce unnecessary energy usage. That, in combination with the highly efficient filters and the chemical-free water treatment system in the units, helped the hotel achieve optimal energy performance.”

“For many hotels, HVAC can be the number one issue with inefficiencies,” says Rod Temistocle, area director of engineering for Kimpton Hotels. “With the units we currently have in place, Hotel Palomar has seen a significant reduction in energy use.”

Photo by Skywall Photography, courtesy of ClimateMaster

Water-source heat pumps were placed in the ceiling to save space and maintain the integrity of the historic Palomar Hotel in Philadelphia, Pennsylvania.

Opening Up Boundaries

The Global Development Research Center (GDRC), a non-profit think tank that carries out initiatives in education, research, and practice, lists 44 benefits to collaborative learning. According to the GDRC, the first 10 reasons that collaborative learning² provides educational benefits are:

1. Develops higher level thinking skills

2. Promotes student-faculty interaction and familiarity

3. Increases student retention

4. Builds self esteem in students

5. Enhances student satisfaction with the learning experience

6. Promotes a positive attitude toward the subject matter

7. Develops oral communication skills

8. Develops social interaction skills

9. Promotes positive race relations

10. Creates an environment of active, involved, exploratory learning

Flexible spaces that promote collaborative learning provide better learning environments and continue to be an important part of the design laundry list requested by teachers, administrators, and parents.

According to Matt Thomas, marketing manager at NanaWall Systems, “the current trend in interiors for the schools of the 21st century is to provide shared space, brighter interiors with natural daylight and fresh air. When you have flexibility in room configurations and access to daylight and fresh air, the architect can design cost-saving, smaller buildings with reduced lighting and ventilation fan equipment. The increase in exposure to natural environments has been shown to increase learning and behavior in schools. A sustainable building removes barriers to learning.”

Using opening glass walls enables the separation of smaller groups for discussion, group projects, quiet zones, advanced or remedial work, test centers, teacher-assistant led groups. It allows teachers to monitor multiple activities in separated spaces and promotes teamwork. Parents or visitor volunteers in the classroom, can use these areas to work independently with students. Flexible workspaces can provide rooms that have common storage space for shared books, supplies, computers, and reduces redundant purchases. Joining two or more classrooms with shared space allows teachers to configure space to meet their needs and allows for a quick and easy transformation for shared classroom management or cool off/recovery areas for behavioral and emotional issues or disciplinary actions.

Opening glass walls can also facilitate daylight harvesting. Sharing daylight between spaces reduces the need for electrical lighting and provides access to the changing environment outdoors, which, according to researchers, can increase test scores and improve student behavior. Frameless walls are also available that comply with ADA regulations. These walls can be selected on single tracks to slide, pivot, fold or pivot at a center point maximizing flexibility for optimal configurations.

However, not all glass walls and partitions have the same performance capabilities. The high impact of day-to-day use and abuse in a school setting or in other commercial settings require the designer specify to meet high performance ratings. New glass walls provide even more options for flexible configurations meeting higher standards. They can be specified as curved walls, meet acoustic criteria, and have higher energy ratings to control heat loss/gain.

More architects understand that the durability and performance of a system is an important aspect of sustainability. To specify an opening glass wall to provide outdoor access, architects are requesting information on the system's thermal performance. Opening walls should be durable and provide good thermal protection when these units are exposed to snow, rain, wind loads, extreme temperatures, etc.

When designing interior spaces with opening glass walls, the architect should require that the shared space should not affect the ongoing classroom activities. Opening glass windows can be specified with Sound Transmission Class Ratings (STC) that meets the criteria for the protection of adjacent spaces from unwanted noise.

Fresh Air Dining Shouldn’t Sacrifice Thermal Comfort

Located in the Salt Lake metropolitan area, Station Park is a new mixed-use transit hub and destination shopping mall with places to eat, shop, and play. The design team focusing on the Park Stone Restaurant decided to expand the restaurant area so it would spill out into the park area which contains a state-of-the-art dancing water feature equipped with LED lighting. This 62-acre complex will also include a new 125-room hotel and over 150,000 square feet of offices adjacent to the Fountain Square.

In the design of ParkStone Wood Kitchen, which features wood-grilled meats and veggies and a vast beer menu, the owner and design team decided to go with an open floor plan and extend the seating to an outdoor patio that would also be usable during three seasons. Designers at Architectural Nexus, architects for the entire Station Park development worked with Perkowitz & Ruth Architects on the Park Stone project. They selected a high-performance wood folding wall system to get the “bring-the-outdoors-in aesthetic” desired by the owner, California native Allan Gantes. The entire patio, which is replete with sofas and a fire pit to give the hotspot a casual, Rocky Mountain vibe, can be enclosed quickly and easily with an opening wall system.

According to project architect Aaron Arbuckle, AIA, LEED AP, “For this new project we wanted to expand the restaurant area so it would, in a sense, spill out into the park area. This makes it ideal for three-season dining.

Diners are comfortably seated even in the winter at the Park Stone in Station Park because of the efficient opening window wall with thermal breaks and high U-values. In the summer, patrons dine outside and have a view of the adjacent park. New restaurants are boosting their revenues by expanding their seating capacity to the outdoors. Diners' experiences are enhanced by access to the outdoors that does not sacrifice thermal comfort in the winter.

Photo courtesy of NanaWall Systems

Diners are comfortably seated even in the winter at the Park Stone, a restaurant near Salt Lake City, because of the efficient opening window wall with thermal breaks and high U-values. In the summer, patrons dine outside and have a view of the adjacent park.

Photo courtesy of NanaWall Systems

Opening glass wall section showing thermal insulation that protects against thermal bridging