CentaFlex Zero-VOC Liquid Urethane Rubber Coating System for Mechanical Room Floors

PART 1 - GENERAL

1.1 SUMMARY

This section describes requirements for furnishing and installing a durable waterproof membrane consisting of 100%-solids urethane elastomer coating system for concrete mechanical room floors. It is chemically cured, contains no solvents, allows for high film build and has excellent toughness and elongation. This system meets the requirements of Class A rating on noncombustible substrates when tested under ASTM E-108/UL 790.

1.2 RELATED SECTIONS

1. Cast -In-Place Concrete: Section 03300
2. Flashing and Sheet Metal Section: 07600

1.3 SUBMITTALS

1. Product Data: Submit manufacturer's standard submittal package including specification, installation instructions, and general information for each waterproofing material.
2. Applicator Qualifications: Submit current "Qualified Applicator" certificate from the specified waterproofing manufacturer.

1.4 QUALIFICATIONS

1. Primary waterproofing materials shall be products of a single manufacturer. Secondary materials shall be recommended by the primary manufacturer. Manufacturer shall have a minimum of 10 years experience in the manufacture of materials of this type.
2. Applicators shall have a minimum of 5 years experience in the application of waterproofing materials of the type specified. Applicator shall possess a current "Qualified Applicator" certificate from the specified waterproofing manufacturer.
3. Pre-Installation Conference: Just prior to commencement of fluid application waterproofing system, meet at site with a representative of coating manufacturer, waterproofing contractor, general contractor, architect and other parties affected by this section. Review methods and procedures, substrate conditions, scheduling and safety.

1.5 DELIVERY, STORAGE AND HANDLING

1. Store coating materials in original unopened containers at 60°-80° F (16°-26°C) until ready for use.
2. Follow special handling or storage requirements of manufacturer for cold weather, hot weather, etc.
3. Safety: Refer to all applicable data, including, but not limited to MSDS sheets, PDS sheets, Product labels, specific instructions for specific personal protection requirements.
4. Ventilation: Provide adequate ventilation to prevent hazardous fume accumulation during application.
5. Environmental requirement: Proceed with work of this section only when existing/forecasted weather conditions will permit application to be performed in accordance with manufacturer recommendations.

1.6 WARRANTY

Provide a 5-year warranty, jointly between the manufacturer and the contractor. Contractor must be eligible for, and make application to Gaco Western prior to the start of work under this section.

PART 2 - PRODUCTS

2.1 MANUFACTURERS

1. Acceptable Manufacturers: Gaco Western, Inc. or Approved Equal

2.2 MATERIALS

1. Zero VOC Urethane Coating: Gaco Western CentaFlex U-62 Series 100% solids, two component, chemically cured urethane rubber.
2. Zero VOC Sealer: Gaco Western E-5481 Epoxy two-component 100%-solids urethane concrete sealer.
3. Flashing and Joint Reinforcing Fabric: Gaco Western 66B and 66S fabric.
4. Aluminum Oxide or Silica Sand: 24 or 30 mesh (.74 mm or .59 mm)
5. Misc. Accessories: All items incorporated into this system shall be compatible with and approved by coating manufacturer.

PART 3 - EXECUTION

3.1 EXAMINATION

1. Verify that substrate is ready to receive work, surface is clean, dry and free of substances which could affect bond.
2. Verify that the concrete meets the requirements of the coating manufacturer. Refer to General Instruction Section GW-2-1 for complete information on the installation and finishing of concrete.
3. Do not begin work until concrete substrate has cured 28 days, minimum.
4. Verify that all other work involved with this area, done under other sections, has been completed and accepted by the architect and general contractor prior to starting the waterproofing application.

3.2 PREPARATION

1. Clean substrate to remove any and all surface contaminants. Refer to General Instructions Section GW-1-1.
2. Mask off all adjoining areas that are not to receive the fluid applied waterproofing.
3. Provide a suitable work station to mix the coating materials.

3.3 INSTALLATION

1. Technical Advice: Installation of this waterproofing membrane shall be accomplished in presence of, or with advice of manufacturer technical representative. Contact nearest regional office for assistance.
2. Primer/Sealer: Apply one coat of Gaco Western E-5481 to all surfaces to receive fluid-applied waterproofing, except areas previously caulked, flashed or fabric reinforced. Apply at rate of one gallon per 150 square feet (4.1 L/15 m2). and allow to dry at least 4 hours, but no more than 36 hours before applying waterproofing.
3. Detail Work: Install approved urethane caulking as required and tool surface smooth. Install Gaco Western fabric reinforced flashing at all changes of plane using Gaco Western U-62 Series Urethane with 66S Tape. Treat cracks in the surface with Gaco Western U-62 Series Urethane and 66B Tape.
4. Urethane Base Coat: Apply one coat of Gaco Western U-62 Series Urethane at a rate of 1¼ gallon per 100 sq. ft. (4.1 L/10 m2), (20 mils (.5 mm) wet or dry) to all areas to receive fluid applied waterproofing, including areas previously caulked, flashed or fabric reinforced. Allow this membrane to dry for at least 12 hours, but no more than 48 hours before applying the non-skid wear course (if required) or finish coat.
5. Urethane/Aggregate Wear Course: Apply one coat of Gaco Western U-62 Series Urethane at a rate of .5 gallons per 100 sq. ft. (2 L/10 m2), (8 mils (.2 mm) wet or dry) and immediately broadcast 4 to 6 pounds (18 kg to 27 kg) of GacoShell per 100 sq. ft. into the wet coating. Back roll immediately to encapsulate the GacoShell.

3.4 FIELD QUALITY CONTROL

1. The contractor for work under this section shall maintain a quality control program specifically to verify compliance with this specification. A daily log shall be kept to record actions in the field.
2. Inspections: A minimum of three (Substrate, Application and Final) inspections, by an approved manufacturer's representative, will be required on all projects requiring a warranty.
3. Thickness: Minimum overall dry film thickness of the completed fluid applied waterproofing will be not less than 20 mils (.5 mm). Thickness including aggregate will average approximately 32 mils (.8 mm).