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Historical buildings restored to their original look and feel can be awe-inspiring on the outside and exquisite within. But, getting to that ultimate state of renewed grandeur, while meeting all the codes and regulations that apply to this special type of construction project, can involve numerous challenges for building designers and installers. Nowhere are these complexities more acute than in the modern mechanical systems that must somehow fit within the confines of structures made long ago to accommodate something far simpler and smaller.
“There are lots of hoops and hurdles the owner of a historical building must jump through during the renovation process,” said Todd Ringgold, a Tulsa-based contractor at Palmer Mechanical, which has made historical renovations a major part of its business in recent years.
Ringgold said high ceilings, at least as high as the original building, if not higher, and plaster walls are musts. But, while the interiors hearken back to an earlier era, all the amenities must be thoroughly modern and efficient, to better attract buyers and tenants. As a consequence, the updates typically include larger bath and kitchen facilities, equipped with the latest conveniences.
Proper performance of those amenities demands an equally modern infrastructure, none of which can be all that visible nor take up much space, lest they detract from the authenticity of the restoration. The updated wiring, ductwork, conduit and piping for the communications, HVAC, electrical and plumbing systems usually must fit snug-tight into the available air space between the floors of these buildings.
“Essentially, we must squeeze a lot of piping into a very small chase,” Ringgold said.
The Palmer Mechanical portfolio contains five historical renovations in Tulsa, spreading over the past decade, including Philtower Building, the former Tulsa City Hall (now being converted into a hotel) and — perhaps the most notable of all — the landmark, $40 million Mayo Hotel project, which was completed in 2009. All were design-build projects that allowed Palmer to do its own system design work, to better match the infrastructure to the radically altered configurations of these buildings after they had been completely gutted.
“In the restored buildings, the newly enlarged bathrooms and kitchens don’t line up from one floor to the next as neatly as they did in the older structures with their simple, tub-sink-toilet layouts,” said Ringgold, who has served as Palmer’s project manager on each of these jobs. “That’s because the new bathrooms usually include large, marble-and-tile showers with whirlpool tubs, marble-topped vanities, and bigger closets.”
While carving out additional space for larger, better-appointed bathrooms, Ringgold and his crews still must leave enough room for equally well-appointed kitchens, living areas, bedrooms and as so forth. As a result, Ringgold said that the piping, wiring, venting, etc. have to be completely redone.
The design-build process gave Palmer Mechanical another advantage: more decision-making authority over the types of building materials used on the project. This has enabled the company to use a different type of plumbing system: crosslinked polyethylene, or PEX-a, pipe rather than copper.
PEX-a’s flexibility and ease of use is a major laborsaving, stress-reducing improvement over the rigid copper and rigid plastic systems of the past. Just as the inherent characteristics of copper led to its replacing old-fashioned galvanized steel and cast iron in years past, the significant benefits of flexible PEX-a have made it not only the preferred choice for commercial applications in general, but also the ideal solution for meeting the demands of historical renovation.
Using the “Engel” manufacturing method, which results in a very high degree of molecular crosslinking, PEX-a offers exceptional durability and flexibility. That flexibility, combined with the availability of PEX-a in long coils, eliminates many of the fittings and connections required in rigid metal and plastic plumbing systems. Eliminating fittings means less material, less installation labor and fewer potential leak points, all of which results in more efficient installs and lower costs.
The Mayo, located in downtown Tulsa, was built in 1925 by the brothers Cass A. and John D. Mayo. The original 18-story tower housed 600 guest rooms — each with its own ceiling fan, a major selling point — and served as a gathering place for Tulsa high society and visiting dignitaries and celebrities. Oilman J. Paul Getty once made The Mayo his full-time home.
In 1980, the venerable hotel achieved recognition on the National Register of Historic Places, even as it struggled to regain its fading, grand hotel luster. Following the last of several botched attempts at restoration, The Mayo sat idle for nearly two decades until 2001, when it was bought for $250,000 by the Snyder family, whose vision was to restore its special character and former glory. The final result is now an elegant mix of hospitality and residential spaces, with 102 hotel rooms and 70 apartments, ranging from 450 to 1,200 square feet and offering views of the nearby Arkansas River, the BOK Center and downtown Tulsa.
In its own way, The Mayo’s refurbished infrastructure is as impressive as its restored interiors and exterior. Galvanized steel mains deliver cold water to each floor of the hotel, with the run-outs to the living spaces made of Uponor AquaPEX PEX-a pipe, furnished by Uponor North America. Each residential space has its own water heater, while hot water for hydronic space heating is delivered by one of the boilers located in a basement mechanical room. This setup entails two piping systems on each floor — domestic hot water and space heating — each also made of PEX-a and running from each residential unit to one of two nearby mechanical rooms on each level.
“We installed about 70,000 feet of AquaPEX for the plumbing system and another 51,000 feet of Wirsbo hePEX for the hydronic heating and cooling runs,” Ringgold reported, who led a 20- to 25-man crew during an installation process that spanned approximately five months.
It is important to note that the heating and cooling piping, Wirsbo hePEX (also manufactured by Uponor North America), features a special oxygen barrier to protect ferrous components in the system from corroding through contact with oxygen in the water. All this piping — nearly 23 miles worth — had to be stacked or racked with the electrical, fire sprinkler, venting and communications lines in chases concealed above the hallways inside the nine-foot-high ceilings on each floor. The dimensions of these overhead chases, Ringgold estimated, were only three or four feet wide and four or five inches in depth. This was hardly big enough for a grown man to crawl through, let alone one charged with the task of making leak-free pipe connections.
“That’s where PEX-a really comes into play for us,” Ringgold said.
Installing long straight runs of PEX-a pipe of up to 140 feet within these cramped quarters was challenge enough. But, thankfully, no pipe connections were needed with PEX-a, which comes in coils up to 1,000 feet in length. This is in sharp contrast to using straight lengths of copper, which would have required soldering a pipe joint every 20 feet.
“Shoehorning an installer into those little spaces with a torch would’ve been just asking for trouble. Why mess with fire in tight spaces, especially one with hard, plasterboard ceilings?” Ringgold asked.
Ringgold figured that using time-consuming copper would have boosted installation costs by as much as 30 percent.
“You could hardly afford to do the job with copper, with all the fittings you would need for your offsets,” Ringgold said, noting that more connections, by definition, equals a greater potential for leaks.
The special characteristics of PEX-a pipe also deliver other time- and money-saving advantages in a large and complex renovation project, such as The Mayo. Ringgold recalled one especially difficult part of the installation in which the layout called for routing plumbing lines through an attic area above the hotel ballroom. This space was jammed with electrical gear, so his crews needed to circle the lines around this equipment.
With copper, every change in direction necessitates cutting the pipe and soldering two connections. With PEX-a, which has the smallest bend radius of any type of PEX, it’s simply a matter of bending the pipe in the desired direction. In this instance at The Mayo, the ease-of-use advantage had benefits beyond speed, given the precarious location of the attic above a set of stairs.
“Instead of trying to sweat copper connections while perched 25 to 30 feet in the air over a stairwell,” Ringgold said, “we were able to maneuver a continuous length of PEX-a pipe through the hangers in much less time and with less hazard and cost.”
In places where pipe joints are unavoidable, making them is relatively easy when you capitalize on the natural ability of PEX-a to expand and contract, using an “ASTM F1960 cold-expansion connection.” The resulting permanent connection holds tight in tests up to 1,000 pounds of pull force with no deburring, no torches, no flux, no solder, no cements and no curing or cooling time. In addition, since the pipe is expanded before the fitting is inserted, it’s impossible to “dry-fit” the connection, eliminating the possibility of incomplete fittings and the resulting blow-off leaks.
Ringgold noted, “The flexibility of PEX-a gave us not only much more maneuverability for the install, but also far fewer chances for problems, post-installation.”
The Mayo project was Palmer Mechanical’s first experience using PEX-a pipe for heating and cooling lines, and Ringgold was impressed by the fact that his crews did not need to insulate the pipe. Not only does PEX-a resist condensation on cold-water lines, but it also offers superior heat retention in hot-water supply runs. At The Mayo, the system-temperature levels were such that no insulation was needed.
Ringgold and Palmer Mechanical put a high premium on flexibility in this type of work, which is why the company has come to believe that PEX-a is the way to go for plumbing and heating systems. Although Ringgold came to embrace PEX-a fairly quickly after his initial experience in 2005, he knows that some contractors, engineers and owners remain unpersuaded. Among those working with the tools, the biggest objection he has encountered has been an aesthetic complaint.
It is an objection that Ringgold finds bewildering when set against the economic arguments for PEX-a, including the comparatively high and rising cost of copper, as well as the fact that copper is a prime target for jobsite theft.
Still, some of the trades remain skeptical of plastic in general for reasons beyond appearance. Many of these professionals hesitate because of their long, negative memories of polybutylene (PB) and the hardships failed PB systems caused builders and installers around the country in the early 1990s. But the problems of PB have nothing to do with PEX-a, which was first commercialized in Europe in the 1970s and came to North America in 1984.
Ringgold pointed to the length of the warranty for PEX-a versus copper. In Uponor’s case that protection extends 25 years on both the Uponor AquaPEX pipe and the ProPEX fittings when installed by a factory-trained professional.
The most important assurance of all for Ringgold was the trouble-free performance of the systems Palmer Mechanical has installed over the past eight years.
“We have seen no problems and no complaints with the PEX-a systems on any of these historical-renovation projects in Tulsa, including the very first one that served as our learning curve," Ringgold said.
Marriott International, Inc.
Provided by Affiliated Steam & Hot Water, Armstrong International
In 2010, Marriott International announced that it selected The Brain Model DRV80 Digital Re-Circulating Valve from Armstrong International, as its corporate standard domestic hot water temperature control device for all Marriott branded hotels. Marriott selected the DRV80 because it is a fully digital recirculation valve (DRV) designed specifically to be the primary water temperature controller in a continuously pumped recirculating hot water system. The DRV80 can control within +/- 2°F (1°C) accuracy and provide flow capacities from 0-150 gpm (0-568 lpm).
The Marriott’s January 2011 Design Standard (Module 15B) requires one Model DRV80R-BS1-DS Digital Re-Circulating Valve from Armstrong for hot water systems with a maximum simultaneous demand (MSD) < 78 GPM. Systems with a MSD up to 156 GPM must be provided two DRV80R-BS1 valves that are piped in parallel. That standard notes that designers and installers may also consider a fully pre-piped “Digital Mixing Center” (DMC1-BS1-DS & DM2-BS1-DS).
The Marriott’s 2011 standard pertains to New Construction and Engineered Renovation projects. The previous Marriott Design Standard called for two Armstrong DRV80 digital mixing valves piped in parallel for each hot water system. Installation was to be piped and pressure tested and complete with isolation valves, strainers, mixed return flow indicator, check valves, thermometers, mixed outlet water sensor per manufacturer. Systems were to have remote set point adjustment capability for connection to Building Automation System (BAS).
In 2013, Affiliated Steam & Hot Water completed an install of The Brain at the Marriott in Milwaukee, Wis. The hotel is an AAA, 4-Diamond hotel with 205 rooms.
Digital Re-Circulating Valve (DRV)
For systems with a maximum simultaneous demand (MSD) ≤ 78 gpm (295 lpm), one (1) each of The Brain Model DRV80R-BS1-DS Digital Re-Circulating Valve from Armstrongmust be provided. For systems with a MSD up to 156 gpm (591 lpm) two DRV80R-BS1-DS must be piped in parallel.
Valves must be installed exactly as indicated in the following installation schematics:
• One DRV80R-BS1-DS – Installation Schematic Number S10782-1
• Two DRV80R-BS1-DS – Installation Schematic Number S10782-2
DRVs must have integral remote set point adjustment capability and be programmable two level high temperature alert feature, one of which, if enabled, will both alert and cause the valve to enter “safe mode.” There must also be the integral LED display to indicate set point temp, operating temp and self diagnostic error messages.
Each DRV80 has to be supplied with an independent hot water monitoring system (BrainScan 1 - suffix BS1), which connects directly to the valves integral serial port. The HW monitoring system must offer hot inlet, cold inlet and mixed outlet temperature readings with a web interface and be configurable to connect directly to a resident BAS via BACnet, LonWorks and Modbus protocols. Designers and installers can also consider a fully pre-piped “Digital Mixing Center” (DMC1-BS1-DS & DM2-BS1-DS).
The Brain system provides two Armstrong DRV80 digital mixing valves piped in parallel for each hot water system. Installation has to be piped and pressure tested and complete with isolation valves, strainers, mixed return flow indicator, check valves, thermometers, mixed outlet water sensor per manufacturer. The system must have remote set point adjustment capability for connection to Building Automation System (BAS).
La Quinta Inns & Suites
Provided by Blackall Mechanical, Inc., Eco Smart Energy, LLC
Blackall Mechanical, Inc. is a factory-authorized installation firm, located in Dallas, Texas, which works closely with La Quinta Inns & Suites in North America. Bill Seel is manager of the Plumbing Division at Blackall.
“La Quinta has always been proactive when it comes to energy savings and green technology. The customer is the most valuable asset La Quinta has,” Seel said. “The customer’s experience while staying at the hotels is the primary concern.”
Typically, Blackall’s hotel clients budget for boiler replacements. Most use the standard gas fired boiler systems to heat domestic hot water as well as laundry, and at most locations has a redundant boiler, should one fail.
In a case in Little Rock, Ark., one of Blackall’s LaQuinta Inns & Suites clients had an unforeseen failure of the primary system. Going back with a conventional change out would mean they would have to shut down, due to the size constraints of typical gas fired boilers. This would mean lost revenue due to the inability to provide hot water to most of the available rooms for rent.
After Blackall presented the Sun Equinox Hot Water System to them, which can be installed while keeping the backup system running, they saw the value in the Engineered Hot Water System. Eco Smart Energy, LLC is the distributor of the Sun Equinox System (also known as Rotex in other parts of the world). The system has been called one of the most efficient hot water systems available in North America.
Each system is engineered to customer specifications, and applicable for every hot water application on the market. Sun Equinox Systems can be used as a pre-heat system for pools, spas, motel and hotel laundry rooms, or engineered to meet every hot water demand in a 600-room hotel. Typical savings range from 25 to 60 percent reduction in gas or electricity bills. Sun Equinox Systems have been installed throughout the world, produce ample supplies of hot water, and substantially reduce operating and maintenance costs.
Taking up less floor space and being less labor intensive to install, with the Sun Equinox System project at the LaQuinta Inns & Suites property there was no business interruption and a smooth retrofit was completed. This allowed Blackall to pull the remainder of the old system out after the system was on line.
After months of monitoring the operational cost of the new system against the old system bench mark, a senior representative from LaQuinta Inns & Suites reported back to Blackall with praises.
“We’re delighted to be distributing the new, innovative and highly efficient Sun Equinox Heating System to our customers across the continent,” said Rodney Thornton, of Eco Smart Energy. “It’s the world’s best heating system, with thousands of installations worldwide.”
With the solar component, Blackall’s customers are enjoying great savings. Blackall now has monitoring solutions as well, which allow customers to track the solar component’s contribution to the overall efficiencies of the system.
“In the current economic climate, many businesses make major infrastructure choices based entirely on initial cost, without considering the true cost of ownership over the life cycle of the equipment they are choosing to install,” Thornton said. “However, with significant Federal Tax Incentives, accelerated depreciation, greatly reduced maintenance costs, and 25 to 60 percent reduction in gas consumption, the Sun Equinox Heating System’s return on investment is very attractive and simply makes good business sense.”
Niagara County Community College’s Niagara Falls Culinary Institute, in Niagara Falls, N.Y., fully engages the community both academically and economically. The institute formed via the adaptive reuse of the Rainbow Centre Mall building in Niagara Falls.
The project is 85,000 square feet and harnesses the building’s atrium gathering space, which is 85 feet tall. The space showcases the institute’s educational, production, and service capabilities to students and visitors. Designed to resemble an outdoor plaza, and featuring an exposed elevator, this central public space provides access to a fine-dining restaurant and lounge, delicatessen, pastry shop, Barnes & Noble bookstore, combined wine boutique and mixology lab, and culinary theatre.
Six state-of-the-art culinary teaching spaces, designed to accommodate current and future techniques and technologies, provide the education and experience needed to operate the foodservice venues. A pastry production lab provides daily goods to local businesses. With celebrity chefs on stage in the theatre and full beverage service in the wine boutique and restaurant, the institute is a popular community destination. A sophisticated interior design palette incorporates warm tones and nature-based patterns representative of the Niagara Falls region.
The Rainbow Centre was a former parking garage that was converted to a shopping mall and food court, after standing vacant for nearly 20 years. The transformation of the center posed many challenges for the global design firm CannonDesign. CannonDesign creates design solutions to great challenges facing its clients and society.
The firm’s culture is based on collaboration, teamwork and mutual support; where all members of the team are individually and collectively committed to each other. The firm believes its combination of proven abilities to define a vision, create a compelling image, effectively communicate ideas, build consensus, develop options and realistic costs, navigate regulatory approvals, and deliver technical quality, all contribute to the realization of a successful project.
Close communication among owner, architect, engineers and construction manager was crucial in achieving a complicated demolition and abatement of The Rainbow Centre. Detailed engineering studies were conducted with the food service equipment consultant to ensure adequate supply of gas, power and water to the culinary program.
CannonDesign’s engineers worked with the local utility company to supply the proper volume and pressure requirements. This service was extended over a quarter mile to the facility. Concrete floor decks were replaced to address dramatic changes in structural loading. A 2,000-pound capacity grease intercepting system was installed at the exterior of the facility for easy maintainability and to properly capture and retain grease waste from food service equipment, teaching spaces and labs, and the full-service restaurant.
Entirely new engineering systems were installed, including plumbing, fire protection and HVAC systems capable of meeting all the owners’ requirements for the renovated space. Plumbing engineers designed innovative piping installations to work around the restricted penetration options within the original, and untouched, precast floors.