Trump Village Section 3 Balcony and Façade Repair Project: Repairing Damage from a Hurricane/Harsh Elements and Minimizing Future Damage
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Trump Village Section 3 Balcony and Façade Repair Project: Repairing Damage from a Hurricane/Harsh Elements and Minimizing Future Damage Site History When Trump Village opened its doors in the Coney Island section of Brooklyn in 1964, it transformed a neighborhood into a vibrant community of seven (7) 23 story, brand new state of the art brick towers with modern one, two-and three-bedroom co-op apartments, many with balconies and views of the ocean and the skyline of lower Manhattan. Coney Island is the home of the famous Cyclone in Luna Park, the NY Aquarium, the Brooklyn Cyclones and new Ford Amphitheater at the Boardwalk not to mention Nathan’s Famous hot dogs, Mermaid Parade and miles of ocean front beach. The complex, just steps away from the attractions, was built by Fred Trump on the site of the former Culver Depot and designed by architect Morris Lapidus. The construction cost was estimated at $70 million and it was supported by the New York State Housing Finance Agency through public bonds issued by the state of New York, coupled with tax exemption. Five out of the seven buildings were part of the Mitchell-Lama Housing Program under the supervision of the State Division of Housing and Community Renewal. In 2007, as the mortgage was paid off, the cooperators, voted to become a private cooperative. This created a boom in the real estate value of the cooperative. Trump Village Section 3 (“TV3”) had broken off to establish their own identity. TV3 consists of three (3) 23-story high-rise buildings boarded by 5th Street and Neptune Avenue. The brick cavity wall construction buildings consist of reinforced concrete floor and roof plates. The edges of the concrete, along with the balcony curbs, were subsequently cladded with aluminum. There are over 1,200 dwelling units and over 600 shared cantilevered balconies. During October – November 2012 Hurricane Sandy created havoc on the Coney Island community as the ocean waters surged and flooded the site and buildings. The tidal currents pulled underground soils and sand back out to the ocean creating settlement through the area. Over the years, the briny air and fluctuating high winds carried corrosive elements to the building façades and balcony concrete. During the years after Sandy, numerous façade and patch repairs were performed on the building. However, at this time, it was determined that the balcony rail post and pockets were unstable. Previous load testing and reports confirmed this, and the buildings were declared UNSAFE and Local Law 11 inspection reports were filed, as such, with the NYC Department of Buildings. Also, a number of the balcony railing heights and spacing were slightly off from the new Building Code requirements. Many of the rail post pockets had deteriorated causing the railings to become loose from their grouted pockets and deteriorated aluminum sleeves. Many exfoliated windowsills and various areas of the brick/masonry façade were noted. Along with the damaging effects caused by the hurricane, the existing building drawings were also casualties of the flood water and were completely destroyed. Investigation Sidewalk shedding and fencing had been installed all around the property accessways for pedestrian protection. As a result of all the testing and studies on the building construction, and the deteriorated condition, it was determined that an extensive repair campaign would be required, mainly due to the corrosive damage to concrete balconies, railings and partitions. It was during this time that the Owners decided work needed to be started so as to reduce the long term monthly rental fees on the shedding. The rental fees would keep accruing until the work required was performed and the buildings could once again be declared as SAFE with the NYC DOB. Initial probes were performed on all three (3) buildings. The aluminum cladding was removed from the concrete balcony curbs along designated drops on the buildings. PHOTO 1: Typical building with sidewalk shedding. The exposed areas were then sounded and deterioration, including concrete spalling with rusted reinforcement, noted and documented. The probe and core locations were designated randomly to determine the extent of chlorides within the concrete around the balcony curbs and floor slabs. Concrete cores were taken and sent to a testing laboratory for observation and analysis. The cores taken close to the outer curbs indicated a larger percentage of chlorides with lesser amounts as you traveled along the slab towards the building. Balcony drains and connections at the building were probed to check construction and condition. Some balcony drains in the probed areas required replacement. PHOTO 2: Concrete balcony curb and steel reinforcement damage, along with loose railings, evident after removal of aluminum cladding. Reinforcement originally placed with insufficient coverage was present at most curbs. This reinforcement was also in contact with aluminum rail post sleeves. Due to extensive deterioration, improper reinforcement placement and the desire for a lasting repair, it was decided to replace rather than patch the concrete curbs. Construction Repairs Construction repair documents were prepared and sent out for bidding. The reinforcement in the existing curbs was replaced/augmented and curb dimensions were increased to provide code required coverage for the reinforcement. Low shrink mix was specified for the new curb with low water cement ratio and lower Portland cement content. The main scope of the contract called for a complete replacement of the balcony curbs, railings and partitions. Also included were façade repairs and replacement of many of the exfoliated slate sills. Drawing 1: Detail sheet of curb replacement and rail post installation. As cooperator’s apartments were barricades/closed-off during the work, the railings were removed, and concrete curbs demolished. Demolition of the concrete revealed additional concerns with inadequate anchorage of the reinforcing steel cage which formed the concrete curb. PHOTO 3: Balcony curb demolition showing steel reinforcement cage. Additional design details were required to accommodate the existing condition and new steel was needed to supplement and strengthen the curb. Formwork was installed to accept the new concrete and all formwork and reinforcement was inspected for conformity. PHOTO 4: Shoring installed at balcony floor slabs and new concrete curb formwork. Strict adherence to the concrete design mix was critical. A 5000psi f’c was specified. Fresh concrete was tested for slump and air entrainment and water content. As pumping could not be performed up the 23-stories the mixed concrete was hoisted in buckets to the be placed in the new curb formwork. Pencil vibrators were used to consolidate the pour and a wet cure was specified. All Special Inspections were performed on the concrete formwork, reinforcement, anchorage, concrete and masonry. PHOTOS 5 & 6: On-site concrete slump test and air-content testing. PHOTO 7: Concrete being moved in buckets from truck to scaffolds via conveyor line. PHOTO 8: Concrete being pumped to lower floors. PHOTO 9: Placing new concrete in new curb forms. PHOTO 10: Wet curing concrete. After curing, forms were removed, and the surface rubbed to fill any voids and pinholes. PHOTO 11: Railing anchors undergoing pull out testing. In addition, new steel reinforcing dowels tying the existing steel cage to the slab, to create an integral system, were installed and tested. PHOTO 12: Completed concrete curb facia with top of curb surface mounted railing. PHOTO 13: Completed concrete curb with surface mounted railing and partition divider anchorage. Along the scaffold drops, concrete spandrels were repaired throughout the façade and at the roof level, as required. Challenges As the project was performed in a densely populated area with high parking demands, the contractor was able to keep a majority of the parking lot areas open while staying within the NYC B.E.S.T. Squad safety construction requirements. The B.E.S.T. Squad was previously responsible to enforce Local Law 196 safety compliance requirements at construction sites throughout the city but had since been retired at the DOB in 2019 and reorganized into the Construction Safety Enforcement Unit (CSE) and Construction Safety Compliance Unit (CSC)*. Due to the height of the buildings, small batches of concrete at discreet locations were difficult to place with conventional methods while still complying to specifications. Original curb dimensions and reinforcement concerns needed to be augmented to correct construction deficiencies without reducing original useable balcony areas. Logistics of doing work in this vibrant community was key to maintaining required quality without sacrificing a safe construction site. The aim was to replace the concrete with a chloride resistant, low shrinkage mix while providing an aesthetically pleasing result having long-term durability. Conclusion As with the completion of the work, the complete replacement of the balcony curbs and railings will minimize any future major repairs generally required during the subsequent NYC DOB FISP Inspection Cycles. Protective coatings on the balcony facia and floor and ceiling slabs should last for a number of years, and cooperators were also provided with special cleaning instructions for the maintenance of the new pedestrian traffic coatings surfaces. New surface mounted railings will eliminate the typical problems encountered at railing post pockets. As stated in the New York City 1RCNY