Their choice of SlenderWall® from Smith-Midland Precast plays an important role in the successful reconstruction of a critical 1970’s medical facility. Announced on April 16th, 2015, The Nelson/Harvey Building has been recognized as an ACI Excellence award winner.
SlenderWall architectural precast concrete panel system has been chosen as the exterior cladding for the renovation of the 9-story Nelson/Harvey inpatient facility on the Johns Hopkins Medicine Baltimore Campus.
After decades of wear the hand-laid brick envelope of the facility began failing. The architectural firms Wilmot Sanz and Ayers Saint Gross needed a solution that met two criteria: one, that is was lightweight enough to prevent any need for additional superstructure or foundation costs; and two, that the facility would be able to stay operational during the exterior renovation. SLENDERWALL met both requirements. Its 28 lbs. per square foot specification and unique composite construction will allow for the re-cladding to take place without the removal of the old fascia. The 158 SLENDERWALL panels (27,164 sq. ft.) are designed with a factory-applied Endicott brick facing, keeping in continuity with the campus and the original 1970’s exterior. Johns Hopkins also chose to include factory-applied closed-cell foam insulation and the proprietary H2Out advanced sealant system with leak detection. The addition of these options will provide not only savings in time and onsite trades, but insurance against future air and water infiltrations, as well as continuous insulation adding significantly to the enclosure’s thermal performance.
The project will be certified under Baltimore City’s Green Stars program, at the level equivalent to LEED Silver. This is the first healthcare project to seek certification under this program.
In March 2013, SMC began delivery to the contractor, Whiting-Turner. Completion of the cladding portion of the project concluded in June. The short schedule showcased the benefits of SLENDERWALL in reduced times and costs for production, shipping and installation, as well as decreasing the need for some onsite trades.
In April of 2012, Smith-Midland completed a Slenderwall project for the U.S. Army Legal Service Agency Administrative Offices at Fort Belvoir, Virginia. This project for the U.S. Army Corps of Engineers was designed to accommodate a 4-story U.S. Army Legal Service Agency Administration Building and the U.S. Army Legal Services and Army Audit Agency, as well as a 2-story adjacent Courtroom Building.
The project incorporated 33,388 s.f. of the Slenderwall® Architectural Precast Wall System. The facility was designed to be a multi-story command headquarters building and achieved a LEED Silver Certification and hopefully LEED Gold Certification. On another note, this project was our first building designed to meet the Department of Homeland Security and the Department of Defense anti-terrorism force security blast criteria for the construction of all new government buildings. The project was installed in a record 14 days!
A sophisticated design statement employs Slenderwall to create a durable yet lightweight and highly insulating luxury apartment complex, The Alexander, which suggests classic Park Avenue style.
With 300 apartments and many with drop-dead views of the Hudson River and Manhattan skyline, The Alexander – a new and much-coveted apartment building in Edgewater, New Jersey – makes a great first impression. Yet it has as much to offer that’s unseen as there is plainly visible to visitors.
Addressing its site in an open pentagon shape, the building is bigger than it looks. It projects a classic elegance that its developer, Fred Daibes, conceived while touring in European cities like Monte Carlo and Paris. It also has more amenities than the typical high-end multifamily residence, with on-site hotel service, indoor and outdoor pools with private cabanas, a cutting-edge fitness center, yoga and meditation spaces, and an all-inclusive spa. Plus residents can enjoy the billiards and game room, a Hollywood-style screening room, multiple business centers, and a general-purpose room.
There’s more behind the scenes, says Daibes, whose firm designed the project in-house to mimic classic limestone architecture.
Within the bone-white walls enclosing these luxury homes, in fact, is the latest in hybrid precast technology: Slenderwall, a highly insulating yet lightweight combination of concrete with a light-gauge metal frame backup and a spray-applied insulating and barrier layer. In this case, the inspiration came from the United States, says Daibes. “We went to Virginia to study the panel system for a project in another state, and we were impressed by its capabilities,” he says. “So we decided to use the system again for the Alexander.”
Led by the company’s house architect, the respected Vijay Kale, the Daibes Enterprises team developed a schematic design concept that recalls Manhattan’s toney Park Avenue post-war architecture, with the classic detailing associated with the 1940s and 1950s. Inside, Kale laid our big, formal apartment layouts, while the outside was conceived in a buff-colored stone. An acid-etched finish and historical details such as cornices, reveals, and bullnoses completed the elegant, timeless exterior concept that Daibes envisaged.
“The Alexander is very ornate, with lots of ins and outs to create the different types of architectural features of traditional, legacy stone façades,” says Jeffrey P. Wholey, manager of business development with Smith-Midland, the precast subcontractor. “The reveals are designed into the panels to make it look like limestone block that was handlaid, even though it is actually made up of larger panels that are cast in our shop and hung on the building structure.”
In addition to the reveals and cornice details, Daibes and Kale called for two distinct textured finishes on the panels for the same concrete mix. “The contrasting textures make it seem like material has changed color, due to the deeper etching of the precast in some areas,” says Wholey.
As is often the case for his small but successful development company, Daibes saw the unique cladding treatment as a way to differentiate the visual brand of The Alexander. “Everybody’s building modern styles with floor-to-ceiling glass, but our target market shares my tastes,” Daibes explains. “I’ve always been attracted to the older styles of buildings in classic European cities and on Park Avenues. The modern buildings just seem to come and go.” This is true of the clientele buying into The Alexander: Young executives in Manhattan looking for larger apartment sizes – Daibes specified units ranging from 860 to 4,000 square feet – at rents about half of what they can find in New York City.
The finishes and fixtures are similarly high-end, says Fred Daibes: “We have selected granite countertops, subway tile walls, hardwood floors, and white marble bath floors that also capture the look of the late 1980s,” he explains. “Those match the white and stainless hardware of the fixtures, yielding a classic design that feels like a brand-new building would have felt when it opened new in 1910.”
According to Smith-Midland, which makes and licenses the Slenderwall system, this was the first precast building for Daibes Enterprises. The developer had used cast stone, brick and stone masonry for many of its buildings, yet it found the Slenderwall panels attractive for several reasons. Chief among those was the proven durability and robustness of system, ensuring a wise investment for the team.
There were more reasons aside from its resiliency and attractive finishes:
First, Daibes Enterprises chose to have the precast panels insulated with closed-cell foam insulation at the Smith-Midland production facility in Midland, Virginia. “This value-added option offers a savings in both time and labor,” says Wholey. Second,
Second, Slenderwall’s lightweight design – about 30 lbs. per square foot – helped reduce foundation and structure costs, as well as the charges for shipping and installation.
Third, a proprietary 360-degree concrete-to-stud connection isolates the exterior precast concrete cladding from the structural stresses associated with wind loading, steel frame movement, expansion and contraction and seismic shock.
Fourth, the light-gauge steel framing provides an immediate stud assembly for interior walls. With one system, the exterior and interior are provided in a slender, efficient enclosure system.
Fifth, the combination of architectural precast concrete, insulated Nelson® anchors, welded-wire fabric and heavy-gauge stainless or galvanized steel studs offered Kale and Daibes unlimited design freedom.
Construction for The Alexander started in 2010, when apartment vacancies were at an all-time low and rents were steadily creeping upward. Production of the Slenderwall panels started in September 2011 and began to reach the jobsite in the first weeks of 2012. The hybrid panels are matched with some traditional precast panels that were required for certain sections of the building, according to Wholey. In all, Smith-Midland delivered 1,024 panels of either Slenderwall or traditional precast, covering just under 99,600 square feet of façade area.
The resulting 290-unit, nine-story structure has been the subject of much press coverage and realtor buzz, a fact that pleases Daibes. He says that the property – which is named after his son – is being built as a tribute to his father, making it as much a personal journey as a building challenge.
It will be a lasting tribute also, based on the successful track record of the exterior system. Slenderwall is durable, hurricane-proof and opaque, keeping out the sun and the elements. Its fine, architectural surface is valued by architects and yet the panels are favored by engineers for the light weight as compared to traditional, heavier precast. And it’s a green system, says Kale, with a lower carbon footprint than alternatives.
As compared to lighter systems such as EIFS or less adaptable systems such as cast masonry, Slenderwall offers a substantial yet lightweight system replete with insulation, vapor/moisture barriers and interior wall framing – all in a single product. In ways seen and unseen, the hybrid precast and light-gauge steel cladding system benefit a savvy developer like Daibes.
On the production end, Slenderwall benefits the building designers and construction team because it is a consistent, controlled system with predictable installed performance. Precast sections were delivered with pre-applied, closed-cell foam insulation that also acts as a vapor barrier, which contributes to the air- and water-tightness of the structure. That’s on top of 3.5 inches of foam insulation, delivering a consistent R-21 behind each Slenderwall panel hung.
Contractors have remarked on the lightweight panels, which can be hoisted with smaller cranes and equipment that fit more easily on a constrained site like The Alexander’s. Traditional precast elements weigh in at a hefty 78 lbs. per square foot or so, while Slenderwall is only about 30 lbs. per square foot or less. The lighter panels take less time to erect, too. Plus they have the integrated steel-stud framing mounted outboard of the floor edge. After erection, the panels can receive drywall and other interior finishes immediately – no furring or additional walls studs required, which saves perimeter floor space, too.
While many observers think The Alexander is all about its impressive visual brand, the Daibes team knows better: It’s about cutting-edge construction techniques, too.