SECTION 03540

GYPSUM CEMENTITIOUS UNDERLAYMENT

RECOMMENDED SPECIFICATION FOR ORTECRETE® FLOOR UNDERLAYMENT OVER EXTRUDED OR EXPANDED POLYSTYRENE FOAM

PART 1   GENERAL

1.01     SUMMARY

A.   This is the recommended specification for Ortecrete Floor Underlayment over extruded or expanded polystyrene foam.

1.02       SECTION INCLUDES

A.   Ortecrete gypsum cement

B.   Maxxon Floor Primer

C.   Maxxon Overspray

1.03       QUALITY ASSURANCE

A.   Ortecrete Installer's Qualifications: Installation of Ortecrete shall be by an applicator authorized by the Maxxon Corporation using Maxxon approved mixing and pumping equipment.

1.04     DELIVERY, STORAGE AND HANDLING

A.   General Requirements: Materials shall be delivered in their original, unopened packages, and protected from exposure to the elements. Damaged or deteriorated materials shall be removed from the premises.

1.05     SITE CONDITIONS

A.   Environmental Requirements: Before, during and after installation of Ortecrete, building interior shall be enclosed and maintained at a temperature above 50 degrees F (10 degrees C).

PART 2   PRODUCTS

2.01     MATERIALS

A.   Gypsum Cement: Floor underlayment Ortecrete gypsum cement as manufactured by Maxxon Corporation, Hamel, MN . All others must receive prior approval.

B.   Sand Aggregate: Sand shall be 1/8 inch (3 mm) or less, washed masonry or plaster sand, meeting requirements of Maxxon Corporation Sand Specification 101.

C.   Mix Water: Potable, free from impurities.

D.   Foam: Extruded polystyrene with a minimum density of 1.6 pcf (25.6 kg/m 3 ) [Type IV] or expanded polystyrene with a minimum density of 1.8 pcf (28.8 kg/m 3 ) [Type IX]. Both types of insulation must meet ASTM C 578. When the Ortecrete thickness is 1" (25 mm) to less than 1 1/2" (38 mm) the polystyrene board must have 1" (25 mm) [minimum] diameter holes 12" (305 mm) on center [maximum] in all directions for support pedestals.

E.   Polystyrene Primer: Maxxon Floor Primer

F.   Sealer: Maxxon Overspray

2.02     MIX DESIGNS

A.   General Requirements: Ortecrete mix proportions and methods shall be in strict accordance with product manufacturer recommendations.

PART 3   EXECUTION

3.01   PREPARATION

A.   Condition and Cleaning of Subfloor: Subfloor shall be structurally sound. General Contractor shall clean subfloor to remove mud, oil, grease, and other contaminating factors before the installation of the polystyrene.

B.   Fasten the Polystyrene to Subfloor: Polystyrene insulation is to be fastened down by mechanical fasteners, adhesives or a Ortecrete slurry.

C.   Priming Polystyrene: Prime the polystyrene using the Maxxon Floor Primer.

D.   Expansion Joints: Allow joints to continue through the Ortecrete at the same width.

3.02   APPLICATION OF CEMENTITIOUS FLOORING

A.   Scheduling: Application of Ortecrete shall not begin until the building is enclosed, including roof, windows, doors, and other fenestration. Install after drywall and polystyrene installation unless tenant finish requirements identify partitioning after the pour.

B.   Application: Place Ortecrete at 1 inch (25 mm) minimum over polystyrene. At thickness' from 1" (25 mm) to less than 1 1/2" (38 mm) the polystyrene must have 1" (25 mm) [minimum] diameter holes 12" (305 mm) on center [maximum] in all directions for support pedestals. If the Ortecrete is 1 1/2" (38 mm) or greater, the polystyrene does not require the 1" (25 mm) holes. Spread and screed Ortecrete to a smooth surface. Except at authorized joints, place Ortecrete as continuously as possible until application is complete so that no Ortecrete slurry is placed against Ortecrete product that has obtained its initial set.

C.   Drying: General Contractor shall provide continuous ventilation and adequate heat to rapidly remove moisture from the area until the Ortecrete is dry. General Contractor shall provide mechanical ventilation if necessary. Under the above conditions, for 1" to 1 1/2" (25 mm to 38 mm) thick Ortecrete, 10-14 days is usually adequate drying time. To test for dryness, tape a 24 inch by 24 inch (609 mm by 609 mm) section of plastic or high density rubber mat to the surface of the underlayment. After 48-72 hours, if no condensation occurs, the underlayment shall be considered dry. Perform dryness test 10-14 days after pour.

3.03   PREPARATION FOR INSTALLATION OF GLUE DOWN FLOOR GOODS

A.   Sealing: Seal all areas that receive glue down floor goods with Maxxon Overspray according to the Maxxon Corporation's specifications. Any floor areas where the surface has been damaged shall be cleaned and sealed regardless of floor covering to be used. Where floor goods manufacturers require special adhesive or installation systems, their requirements supersede these recommendations.

B.   Floor Goods Procedures: See the Maxxon Corporation's "Procedures for Attaching Finished Floor Goods to Maxxon Underlayments" brochure for guidelines for installing finished floor goods. This procedure is not a warranty and is to be used as a guideline only.

3.04   FIELD QUALITY CONTROL

A.   Slump Test: Ortecrete mix shall be tested for slump as it's being pumped using a 2 inch by 4 inch (50 mm by 101 mm) cylinder resulting in a patty size of 8 inches (203 mm) plus or minus
1 inch (25 mm) diameter.

B.   Field Samples: At least one set of 3 molded cube samples shall be taken from each day's pour during the Ortecrete application. Cubes shall be tested as recommended by the Maxxon Corporation in accordance with modified ASTM C 472. Test results shall be available to architect and/or contractor upon request from applicator.

3.05   PROTECTION

A.   Protection From Heavy Loads: During construction, place temporary wood planking over
Ortecrete wherever it will be subject to heavy wheeled or concentrated loads.

END OF SECTION