ATTACHMENT_NUMBER_001_0040540559_BOST_Faneuil_Hall_Terrazzo_Repair_Scope_of_Work.pdf

Scope of Work Repair of Terrazzo Floor, Stair Tread, Faneuil Hall

Boston National Historical Park

Charlestown Navy Yard Boston, MA 02129

Background Faneuil Hall, one of Boston’s iconic historic buildings is a National Historic Landmark, originally built in 1742. Faneuil Hall was the primary municipal/market building in Boston from 1742-1822 and was the focus of revolutionary activity in Boston in the mid-1700’s, earning the name America’s “Cradle of Liberty”. The building is owned by the City of Boston but is part of Boston National Historical Park and the National Park Service, in partnership with the City of Boston, leads interpretive programs in the Great Hall and has visitor information, a retail outlet and offices in the building. Recently, the retail area and visitor desk were reconfigured and updated to provide more efficient visitor services. Due to movement of fixtures and walls as part of this work, the terrazzo floor is in need of patching and repair. There is also one stair tread on stairs that lead from the main market floor to the lower level that is in need of repair.

Scope of Work The Contractor shall patch holes and refinish the terrazzo flooring, matching the texture and color of the existing floor.

Work for this project includes:

1. Patching and repairing existing terrazzo floors (verified at site visit).

a. 1-repair surrounding new electrical plate in floor, approximately 6”x

12”

b. 32 – approximately 3-4” holes

c. 5- approximately 6” holes

d. 25—approximately 1-2” holes

e. 1- chip on nosing of stair tread, approximately 6”

2. Grinding and polishing of existing terrazzo floors after repairs have been made.

PART 1: GENERAL

1.01 SUBMITTALS

A. Samples for Verification: For each type, material, color, and pattern of terrazzo and accessory required showing the full range of color, texture, and pattern variations expected. Label each terrazzo sample to identify manufacturer's matrix color and marble-chip types, sizes, and proportions. Prepare samples of same thickness and from same material to be used for the Work in size indicated below:

1. Terrazzo: 6-inch- (150-mm-) square Samples.

1.02 QUALITY ASSURANCE

A. NTMA Standards: Comply with specified provisions and recommendations of National Terrazzo and Mosaic Association, Inc. (NTMA).

B. Installer Qualifications: Experienced Installer who has completed terrazzo installations similar in material and extent to that indicated for Project and that has resulted in construction with a record of successful in-service performance.

C. Preinstallation Conference: Conduct conference at Project site.

1. Review methods and procedures related to terrazzo including, but not limited to, the following:

a. Inspect and discuss condition of substrate and preparatory work required for terrazzo repair work.

b. Review and finalize construction schedule and verify availability of materials, Installer's personnel, equipment, and facilities needed to make progress and avoid delays.

c. Review dust-control procedures.

d. Review all cracks and areas needing repair.

1.03 PROJECT CONDITIONS

A. Environmental Limitations: Comply with manufacturer's written instructions for substrate temperature, ambient temperature, moisture, ventilation, and other conditions affecting terrazzo repair work.

B. Close spaces to traffic during terrazzo repair application and for not less than 24 hours after application unless manufacturer recommends a longer period. Control and collect dust produced by routing and grinding operations. Protect adjacent construction from detrimental effects of routing and grinding operations.

1. Provide dustproof partitions and temporary enclosures to limit dust migration and to isolate areas from noise, if necessary.

2. PRODUCTS

2.01 TERRAZZO MATERIALS

A. Cementitious Terrazzo Type: Match existing.

B. Materials:

1. Portland Cement: ASTM C 150, Type 1.

a. Color for Exposed Matrix: Match existing.

2. Water: Potable.

3. Sand: ASTM C 33.

4. Marble Chips: Complying with NTMA gradation standards and as required to match existing.

5. Matrix Pigments: Pure mineral or synthetic pigments, alkali resistant, color stable, and compatible with matrix binder.

C. Mixes: Match existing

2.02 TERRAZZO ACCESSORIES

A. Cleaner: Chemically neutral, liquid cleaner, with Ph factor between 7 and 10, of formulation recommended by sealer manufacturer for type of terrazzo used and complying with NTMA requirements.

B. Interior Floor Sealer: Colorless, slip- and stain-resistant penetrating sealer with Ph factor between 7 and 10, that does not affect color or physical properties of terrazzo surface.

PART 3 EXECUTION

3.01 PREPARATION

A. Clean and prepare substrate to comply with NTMA specifications for type of terrazzo application required. Clean substrate of loose chips and foreign matter.

B. Rout out and remove terrazzo at cracks a minimum of 4 x the width of the cracks along crack lines.

TERRAZZO REPAIR

A. Clean out routed cracks of all dust and loose particles. Patch and fill existing terrazzo using materials and colors that match existing

B. Cut out and replace terrazzo areas that evidence lack of bond with substrate or underbed, including areas that emit a "hollow" sound if tapped. Cut out terrazzo areas in panels defined by strips and replace to match adjacent terrazzo, or repair panels according to NTMA's written recommendations, as approved by Architect.

C. Exercise extreme care to ensure fluids from grinding operation do not react with existing divider or control strips to produce a stain on aggregate.

D. Fine Grinding: Grind all existing terrazzo and new terrazzo patches with 120 or finer grit stones until all grout is removed from surface. Repeat rough grinding, grout coat, and fine grinding if large voids exist after initial fine grinding. Produce surface with a minimum of 70 percent aggregate exposure.

3.05 FINISHING

A. Finishing:

1. Seed additional marble chips in matrix to uniformly distribute granular material on surface.

2. Fine Grinding: Grind with stones 120 grit or finer until all grout is removed from surface. Repeat rough grinding, grout coat, and fine grinding if large voids exist after initial fine grinding. Produce surface with a minimum of 70 percent aggregate exposure.

3.06 CLEANING, SEALING, AND PROTECTING

A. Clean terrazzo after installing and finishing operations are completed, complying with sealer manufacturer's instructions.

B. Apply sealer to cleaned terrazzo surfaces to comply with sealer manufacturer's instructions.

C. Protect terrazzo from damage and wear during construction operation.

3.07 FINAL CLEANING

A. Clean terrazzo as recommended by manufacturer of sealer and machine buff if required.