DALLAS — Luxury and efficiency would seem to sit at opposite ends of the spectrum. Luxury implies a superabundance that verges on wasteful, while efficiency or “eco-friendly” implies either making do with less or going without altogether.
The Museum Tower residential high-rise in downtown Dallas hopes to be a happy marriage of the two. The 42-story, 560-ft. tower is the tallest residential structure to be completed in the city in more than 20 years.
Owned by the Dallas Police and Fire Pension System, the tower includes 115 one-, two- and three-bedroom condominiums that range from 1,800-sq.ft. peid-á-terres to a 9,000-sq.ft. penthouse. Luxury features include striking contemporary architecture, balconies, floor-to-ceiling glass walls, private elevator entry and access to a host of amenities including outdoor recreational areas, a state-of-the art fitness center and 24-hour valet and concierge services.
At the same time, the building is designed to achieve LEED Gold certification. Much of the construction was done with sustainably-sourced building materials. The design maximizes the use of natural light. Faucets and fixtures are low-flow, and toilets are high efficiency.
But far and away the most LEED points come from the heating and cooling system. A total of 335 ClimateMaster Tranquility 20 Single-Stage Series vertical and horizontal water source heat pumps were installed, as well as two Tranquility Large Series horizontal water-source units. Individual units ranging from 3.5-tons to 25-tons were specified for each residence.
The system was designed by Blum Consulting Engineers. “The main goal was two-fold,” said Jack Musick, PE, project manager at Blum, “to be able to sub-meter the electrical usage of each condo unit, and also to achieve an ultra-high level of efficiency with the HVAC system’s operation.”
The company that installed the mechanical systems for the entire building was Don Burden & Associates, a contractor that’s been working in Dallas since 1975. The firm has roughly 150 permanent employees (with some temporary help as the workflow demands) and handles as many as six or seven projects at a time.
“We specialize in new construction,” said Ray Hamilton, senior project manager for Don Burden & Associates. “We do not do service at all. Probably one of the few who don’t, but we’re just not geared for that.”
Don Burden & Associates was on site only a month after the groundbreaking in June of 2010 placing sleeves for some of the larger piping. Now that construction is complete, Don Burden technicians are still out at Museum Tower making modifications to condos as they are sold. Why? Because if luxury means anything, it means having things just the way you want them.
“Every time someone buys [a condominium], they’re basically custom at that point,” Ray Hamilton explained. “They don’t want a cookie-cutter system, so you have to make changes.” Those modifications accommodate everything from hot tubs and whirlpool baths up to full-fledged pools.
Installing the heat pumps —and each condo had a minimum of two —was complicated by tight mechanical rooms, “Basically a closet that’s barely big enough for the unit to fit in,” Hamilton said.
Additionally, all the heat pumps needed to be mounted on spring isolators to help eliminate noise and vibration. “I was honestly a little worried about what would happen at start-up,” Hamilton said. “When we fired the first units there was absolutely no movement whatsoever, and they operated just as they should.”
Because so many heat pumps were being installed at one time, extreme care was taken to keep ductwork sealed during construction to prevent the accumulation dust and debris in the system.
Another problem was getting all the plumbing and piping in above the ceilings. “When you have luxury high-end places,” Hamilton said, “they want the ceilings as high as possible… so one person’s plumbing may be right underneath someone else’s living room where you’ve got a bunch of ductwork running. So you’ve got a lot of different challenges you have to work through.”
Working with BIM helped smooth out some of those problems, making sure all the various system elements were sized, spaced, placed and run just where they needed to be to avoid conflicts and maximize the use of the available space.
Don Burden & Associates also installed the central plant piping and equipment that would feed the water-source heat pumps, including Evapco cooling towers and Aerco boilers. “We’ve got four boilers in there at three million Btus each,” said Hamilton. They also installed all the pumps and heat exchangers and a 100% air ventilation system. Along the way, Don Burden & Associates also fabricated all the piping they needed for the job.
Owners have been moving into the property since December of 2012 and will continue to do so throughout 2013. “We are not getting any calls, complaints or warranty issues,” Hamilton said. “If I’m not getting any warranty calls that’s a good sign.”