This project included what is considered to be the first-ever rebuilding of Guastavino vaults—and one of the largest terra cotta repair and restoration projects in the world.

The original structure was designed in 1914 by Henry Hornbostel for use as an open-air market. The tongue-and-groove terra cotta ceiling, designed by Spanish architect Rafael Guastivino y Esposito, consists of 32 domed, self-supporting four-sided vaults, with dramatic 30 by 30 foot vault ceilings, varying in height from 24 to 44 feet. Four layers of glazed terra cotta tiles set at perpendicular angles in a basket-weave pattern form the “Guastivino vaults.”

A historic landmark, this cathedral-like space was restored, after more than half a century of neglect, to its original use as a public marketplace—the now thriving Bridgemarket. At over 98,000 square feet, it is now home to several shops and a restaurant.

Graciano restoration specialists cleaned stone, repaired surface cracks, pointed granite masonry, and rebuilt entire tile vaults using historical methods of cross-bonded tile built on wooden centers. Where steel supports had rusted and expanded, pushing the terra cotta column covers out of alignment, Graciano removed and reset those tiles. Mortar joints were removed, and new pointing was done to match in terms of color and raised joint tooling. Vaults were waterproofed at the top surface, and cracks were repaired. Thousands of terra cotta tiles were cleaned, repaired and replaced. New tiles from Boston Valley Terra Cotta were kiln fired and color matched to the originals, based upon Graciano’s exacting standards.

Restoration of the arches involved repair and replacement of 65 terra cotta panels and 13 granite base units. In total, the project required over 3,600 terra cotta tiles, 1,728 trim borders and 3,290 ornate field pieces. Finally, Graciano technicians used advanced waterproofing systems and epoxy injection to protect the structure from further deterioration.


“At first glance, the soaring terra cotta barrel-vaulted arches of the restoration project recently completed by Graciano Corporation seem to belong to a church in the south of France,” wrote Eleanor Mancusi in Traditional Building. “What a surprise to discover that the job constituted the Manhattan underbelly of New York City’s Queensboro Bridge.”

Project Details

Name: Queensboro Bridge
Completion Date: 3/22/2000
Owner: City of New York
Architect: Chuck De Santo, Walter B. Melvin Associates
General Contractor: Grow-Perini


Project Included

  • Waterproofing
  • Water Control Injections
  • Water Cleaning
  • Unit Stone Replacement
  • Terra Cotta
  • Stonework
  • Stone Patching
  • Sealants
  • Replacement
  • Repair
  • Reconstruct
  • Pressure Washing
  • Masonry Cleaning
  • Guastavino Vaulting
  • Full Depth Concrete Repair
  • Flashings
  • Expoxy Injection
  • Deck Coatings
  • Concrete Restoration
  • Coatings
  • Cleaning
  • Chemical Cleaning
  • Acidic Cleaners

Glossary Terms

Traffic CoatingsTraffic coatings protect concrete surfaces from wear and tear caused by automobiles, machinery or pedestrian traffic. Most commonly formulated from an epoxy base, these coatings seal out moisture and damaging materials such as salts and oils. They are frequently impregnated with fine aggregates to improve traction and to minimize slipping hazards. Structural RepairsMost concrete structures are reinforced by reinforcement rods (“rebar”) or structural steel. If the concrete skin of the structure has been damaged or has deteriorated, it is frequently necessary to restore or replace the steel substructure. In cases where the building has been built with little steel in the structure, it is frequently necessary to employ and anchoring system to stabilize the building before repairs can be made. ShotcreteShotcrete is a material that combines concrete with compressed air. The mixture is pumped through a hose at high pressure, and is then applied to the desired surface. The force of the air pressure consolidates the material on the surface. Shotcrete can be formulated in one of two ways. The wet method premixes the concrete with water before it is pumped through the high–pressure hose. The dry method involves sucking the dry materials into the application system, combining them with water within the hose, and then apply them to the final surface. SealingSealing effectively closes the porous surface of concrete and makes it more impervious to damaging substances, such as gasoline, oils or melting agents. Sealants are available in clear formulations, for high visibility, high aesthetic areas, or in urethane formulations for high–traffic areas, such as parking decks or industrial floors. Polymer-Modified Mortar RepairsPolymer-modified mortar repairs involve the addition of plasticizers to traditional mortar. These additives improve the mechanical performance of the mortars by improving adhesion qualities, extending working times and improving hot weather workability. Polymer-modified mortars can also offer improved chemical resistance, higher flow, increased flexibility and better levels of compressive and tensile strength. Parking Deck RepairParking deck repairs frequently involve repairs to both the deck surface and to overhead concrete structures that may have been damaged by water infiltration or exposure to melting agents. Repairs can take the form of partial–depth repairs, where a damaged area is filled and sealed, or through–depth repairs, where concrete is removed through to the other side of the damaged surface and then replaced. Repairs may also be made to vertical surfaces clad in concrete or masonry materials, or to overhead surfaces, such as ceilings. Façade RepairsFaçade repairs involve removing damaged or degrading concrete from the surfaces of a structure, stabilizing the repair site, and filling any voids or cracks with new material that has been formulated to match the color and texture of the existing material that surrounds the repair. Façade repairs can also demand the creation of customized forms to allow for replication of cast–in–place detail. DemolitionDemolition entails the removal of damaged or undesired concrete. It is most frequently accomplished with a jackhammer or another piece of pneumatic equipment. Cementitious CoatingsCementitious coatings are generally comprised of Portland cement that has been combined with a vermiculite or perlite premix. These coatings are used to provide fire protection on steel or concrete surfaces, and are typically sprayed on while a structure is under construction. Balcony RepairsBalcony repairs typically involve structural stabilization and replacement of damaged or missing components. In many cases, due to water infiltration or damage from the environment, it is necessary to remove the facing surfaces and decking materials from a balcony, stabilize the steel framework that ties the structure to the building, and then replace the facing surfaces with new or recovered material.