Washington D.C. is known for many “firsts” including, the first live appearance of the Beatles, home of the first Miss America (Mary Gorman, 1921), and the first all-black university (Howard, 1867).

The “Alta at Thomas Circle” – located just a few blocks from the White House – recently entered the list when it became the first certified LEED® condo/mixed-use development in the District of Columbia. But it didn’t start out that way.

The Alta includes 126 residential units from efficiency to 2-bedroom (with a few larger penthouse offerings), plus two retail spaces on the first floor – all packed into an “official” 13 stories, with penthouse roof/deck space all the way at the top, and a 5-level below-grade parking garage.

What sets the Alta development apart from other higher-end condos around the downtown Washington area are its “green” characteristics. Everything from insulation to paints to the water-source heat pump, closed-loop heating-and-cooling system was carefully selected for environmental compatibility and sustainability. These characteristics qualify the building for certification under Leadership in Energy and Environmental Design (LEED) criteria administered by the U.S. Green Building Council.

When the project was first conceived several years ago, the original specifications included equipment that used R-22 refrigerant. It was only very late in the process – during actual construction – that the developer made a strategic decision to switch to water-source units that use EarthPure HFC 410a, a zero ozone depletion refrigerant. This became a key step in achieving the building’s LEED certification. ClimateMaster’s new Tranquility systems, which are built to accommodate HCFC-410a refrigerant, got the nod.

“Everyone was pulling in the same direction to get this done. Otherwise, it probably wouldn’t have happened,” said Al Hedin, senior vice president of development at residential developer PN Hoffman Inc. in Washington. “Initially, we didn’t envision this as a LEED-certified project.

“Three or four years ago years ago when we developed the design, people just weren’t ready environmentally,” added Hedin. “Even today, people may be a little more aware of the environmental needs, but their willingness to spend additional dollars to get a LEED-certified condominium is limited.”

Hedin and others at PN Hoffman nonetheless saw benefits in switching midstream to a LEED-certifiable multifamily/mixed-use concept, using recyclable and sustainable elements on many facets of the building.

“I took a trip out to San Francisco and got some additional information on sustainable development at one of the Urban Land Institute conferences,” continued Hedin. “At that point, we began to take a critical look at how much it would cost to overcome this hurdle, to become LEED-certified.

“There were associated costs, but in this case we determined they’re justifiable because today there’s documented economic benefit when you get into the LEED ‘realm,’ continued Hedin. “In an office setting, its proven that productivity is higher, and that really turns the economics for a long-term cost/benefit analysis.

“But another thing piqued our interest,” added Hedin. “A couple of my development managers and I basically came to the conclusion that this is a way to distinguish our product from other competitors in the marketplace. Because a lot of the multifamily high-rises in D.C. have become homogeneous and difficult to differentiate.

“And we definitely feel that a keen environmental awareness helps to set our product apart from others in our core niche of multifamily condo/residential with a little mixed-use included,” added Melisa Cinarli, LEED AP, Hoffman’s development manager, hired to help manage the Alta project when the developer decided to make it a ‘green’ project, and to seek LEED certification.

Still, it didn’t figure to be a small issue to begin a project with what might be described as a more “traditional” design concept, then suddenly – in the middle of the construction phase – to go green. A number of parameters had to be changed immediately, including the heating-and-cooling apparatus.

“The equipment for this project had not only been spec’d; it had been ordered,” said DMR Associates sales engineer Mike Benson. “When PN Hoffman contacted us and said, ‘What would it take to change this to 410A? We want to change this building to LEED,’ and this is after it’s already under construction – that’s unusual because there’s cost associated with it.

“In other words, the units that use HFC-410a refrigerant – which are more efficient and were brand new at the time – cost more than the initially-spec’d equipment that uses R-22,” added Benson. “But the construction team ultimately came to the decision that if the somewhat higher cost would be feasible, and if delivery of the equipment could happen within the set schedule, we’d move forward with it.”

But since it was a mid-stream change, a realistic approach was settled on, one that permitted ClimateMaster to split the shipment. “We got the enclosures for the units so we could frame around them and we could complete some of the finishes,” said Hedin.

“Then we received the chassis at the last minute and just popped them in place, and made the connections,” added Jac Chiang, project manager for Shapiro & Duncan, the mechanical firm tapped to install all of the building’s mechanical systems. “And that happened about a month before we occupied. “We were crossing our fingers frequently, hoping that everything would arrive in time to occupy the building.

“The mid-stream change to 410a could have potentially been a real challenge,” continued Chiang. “But, fortunately, because of the way the risers and extension couplings are attached to the heat pumps in back, and also that the units were arranged in a ‘stacked’ fashion, from one floor to the next, there were very few changes to deal with.”

“The dominoes fell nicely,” said Benson. “Naturally, there were a few challenges. But, physically, they didn’t have to change anything in the job to do this; the R-22 and HFC-410a cabinets are the same dimension, and with the same water flows.”

The purchase cost for the condos reached up to about $500 per square foot. So it was with that in mind that Rodney Simpson, project manager for Arlington, VA-based GHT, Ltd., the mechanical and electrical engineering firm, pushed for effective utilization of interior space. So GHT designers came up with creative ways to incorporate mechanical and electrical elements into condo unit “furniture” – unobtrusively hiding, and yet availing ready access to building system components.

Some of the other interesting aspects as the building went up had to do with the construction site.

“The Alta is sandwiched between two other structures,” Hedin said. “And one of the challenges in trying to build it was the fact that we only had access to one side. Usually, street frontage is a given. But in this case, we had no rear alley to get to.

So basically, the entire construction operation needed to take place on 14th Street. And that added a fair amount of complication.”

In addition, all buildings in D.C. are subject to the Heights of Buildings Act of 1899, which was amended in 1910 – but which continues to strictly limit the height of every new building that goes up in the District.

“When you look at pictures of D.C., that’s why you don’t see 40-story or 60-story skyscrapers,” Hedin said. “What we call a ‘high-rise’ here is nothing more than a 10-story or maybe a 12-story building. And it’s really kind of a misnomer to call it a ‘high-rise.’ But there are other items that from a code perspective qualify it as a ‘high-rise,’ as opposed to what would be considered a ‘mid-rise’ or a ‘low-rise.’”

The Heights of Buildings Act stipulates an actual footage height that buildings are limited to in Washington – which is roughly 130 feet above what’s called the ‘measuring point’ for the building, setting the cap at 12 to 13 stories.

“So then the question becomes: How many floors are actually on the building?,” said Hedin. “We do unique and creative things to squeeze an extra story out of a building. At the Alta, we have a penthouse structure on top of the building, providing rooftop access and space for mechanical equipment. The penthouse is up 14 floors, but technically it’s a 13-story building – with a penthouse.”

Most of the Alta’s residential units have a single water-to-water heat pump – although each of the penthouse units has two heat pumps. The systems they chose are a water-based closed loop, with boiler and cooling tower both installed on the roof.

“On the heat pump unit itself – in most of these condos – all of the ductwork comes off the top and then elbows out both ways. And the circular-shaped, spiral ductwork is exposed. It feeds into that ‘loft’ feel and look,” added Hedin. So the ductwork itself serves as an important element within the overall residential-environment design.

“We tried to make the heating-and-cooling features a focal point,” said Hedin. “In most cases, the heat pump units are exposed – and we pushed them to the middle of the building.”

Being in the middle of each residential unit also lends aesthetic continuity to the heat pump’s closed-loop system. “Each unit incorporates risers – or the vertical piping,” said Benson. “Essentially, the heat pump units come complete with risers, and they can then be stacked vertically on top of each other from one story to the next.

“So they’re ‘pre-piped.’ And as you construct the building, it’s just like you’re putting blocks together vertically,” added Benson. “One set of pipes fits inside the other set of pipes, and then you go to the next floor – do the next unit, then set the next ones and so on.”

Noise abatement was another advantage for the ClimateMaster systems they chose. “It’s a big issue,” Hedin said, “because we have these heat-pump units that are right in the middle of the living/dining areas. We’re very pleased with the acoustics of the heat pumps.”

“The developer selected the G-panel, which has an acoustical panel on the front of the stack-type heat-pump units,” said Benson. “It’s architecturally friendly, and it has insulation to help dampen the sound.”

“When you install ductwork, you have to put enough oomph and static in the fan to deliver air around the room,” he added. “But the shortest path to your ear for noise is actually out through that ‘return’ panel.

“The G-panel really helps kill whatever sound there is,” concluded Benson. “But our success in noise abatement at the Alta really comes down to a combination of the G-panel and the fact that the heat pumps are quieter and more efficient in the first place.”

Residents at the Alta are undoubtedly finding that living in a green environment is a net positive in many more ways than one.

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