Click To Enlarge	Click To Enlarge

Firm-Fill Gypsum

As a construction professional, you have a lot to think about:

How can I reduce sound transmission in my multi-family housing project to ensure residents' privacy?

How do I bolster the structure's fire resistance?

How can I flatten a substrate to a crack-free surface so that it can be covered with virtually any floor covering?

How do I get compressive strengths up to 1800 psi while keeping costs low?

The versatile and permanent solution to these questions is Firm-Fill Gypsum Concrete. For new construction, repair or renovation, Firm-Fill Gypsum Concrete provides multiple benefits all in one application:

Flattens subfloors
No shrinkage cracks
Lightweight
Easy application: no troweling
Superior STC and IIC ratings
Over 50 UL design number listings
Can be walked on in 90 minutes
Smooth, durable, and joint-free surface
Rapid installation: up to 40,000 sq. ft. per day installed.

PART I GENERAL

1.1 Scope - Specify to meet project requirements.

A. Work included:

1. Firm-Fill Gypsum Concrete
2. Hacker Floor Primer

1.2 Qualifications

A. Firm-Fill Gypsum Concrete must be installed by Licensed Applicators of Hacker Industries, Inc., using approved mixing and pumping equipment.
B. Firm-Fill Gypsum Concrete shall be delivered in original, unopened bags and protected from exposure to the elements after delivery.
C. Install after drywall unless otherwise specified.
D. Before, during, and after installation the building interior must be ventilated and heated to a minimum of 50 degrees Fahrenheit (10 degrees Celsius) to assure completion of the drying process.
E. Compressive strength can be specified from 1200 to 1800 P.S.I (approx. 8.3 to 12.4 MPa)
F. All materials specified hereon shall be approved by Hacker Industries, Inc.

PART II PRODUCTS

2.1 Materials

A. Gypsum concrete - Firm-Fill Gypsum Concrete as manufactured by Hacker Industries, Inc.
B. Hacker Floor Primer and Sealer.
C. Sand - 1/8" (approx. 3mm) or less washed plaster or mortar sand.
D. Water - Portable and free from impurities.

PART III EXECUTION

3.1 Condition of Sub-floor

A. Subfloor must be structurally sound (L/360), broom cleaned, and free of oil, grease or other contaminants.
Specifications
B. All cracks and voids should be filled with a quick setting taping compound to prevent leakage.
C. Before installation, General Contractor shall inspect and approve the condition of the subfloor.

3.2 Priming

A. Plywood/OSB - Spray one coat Hacker Primer using one gallon (approx. 3.78L) per 500 square feet (approx. 47 sq.m).
B. Other substrata - Conditions may vary. Consult your local applicator for recommended floor preparation.

3.3 Mixing Instructions

A. 6 to 7 gallons (approx. 22.7 to 26.5L) of water and sand as specified per 80 pound (approx. 36.3kg.) bag of Firm- Fill Gypsum Concrete.
B. Firm-Fill Gypsum Concrete mix proportions and methods shall be in strict accordance with Hacker recommendations. Firm-Fill Gypsum Concrete is available in two mix designs.

1. 1200-1500 P.S.I (approx. 8.3 to 10.3 MPa) - 1.9 cubic feet (approx. .054 cu.m) of sand per 80 lb. (approx. 36.3 kg.) bag of Firm-Fill Gypsum Concrete.
2. 1500-1800 P.S.I (approx. 10.3 to 12.4 MPa) - 1.4 cubic feet (approx. .040 cu.m) of sand per 80 lb. (approx. 36.3 kg) bag of Firm-Fill Gypsum Concrete.

3.4 Underlayment Application

A. Application - Firm-Fill Gypsum Concrete can be installed at 3/4" (approx. 19 mm) minimum over wood frame, 1/2" (approx. 13 mm) minimum over precast or poured in place concrete. Can be feather edged to zero. Place as continuously as possible until installation is complete.
B. Protection - After installation, temporary wood planking should be placed subject to heavy wheeled or concentrated loads.
C. Drying - Prior to the installation of finished floor goods, the Firm-Fill Gypsum Concrete must be free from any moisture. The General Contractor shall provide continuous ventilation and adequate heat to rapidly remove moisture from the area until the under- layment is dry. Consult flooring contractor for recommended procedures to test for dryness.
D. Firm-Fill Gypsum Concrete is suitable for interior applications only and must be covered by a finished floor material.

3.5 Field Quality Control

A. Slump Test - Firm-Fill Gypsum Concrete shall be tested for slump as it is being installed using a 2" by 4" (approx. 51 mm by 102 mm) cylinder. The patty size should be 8" (approx. 216 mm) plus or minus 1/2" (approx. 13mm) in diameter.
B. Field Samples - Testing of molding cube shall be in accordance with ASTM C472 using split brass molds. Prior to independent sampling, contact Hacker Industries, Inc., to ensure proper ASTM methods are followed. Test results shall be available from the applicator upon request.

A Detailed Warranty Statement Should Be Requested From The Licensed Applicator In Your Area.