GYPSUM CEMENT UNDERLAYMENT
RECOMMENDED SPECIFICATION FOR THERMA-FLOOR; “GREEN” FLOOR
PART 1 GENERAL
A. This is the recommended specification for Therma-Floor “Green” Floor Underlayment.
1.02 SECTION INCLUDES
A. Therma-Floor “Green” floor underlayment with fly ash. Fly ash is a non-combustible mineral
portion of coal generated in a coal combustion power plant.
USGBC LEED Credit Areas Impacted by Therma-Floor “Green” Floor Underlayment
Project Category Credit 3Indoor Environmental Low Emitting Materials EQ 4.1 <0.24 mg/m GREENGUARD CompliantQuality
for Indoor Air Quality Certified?
Materials & Resources Recycled Content MR 4.1 – 4.2 Fly Ash
Local/Regional Materials MR 5.1 Blue Rapids, KS 66411
Camden, NJ 08103
Brunswick, GA 31521
Las Vegas, NV 89124
Local/Reg. Materials MR 5.2 Job site manufactured
with local sand & water
B. Maxxon Floor Primer
C. Maxxon Overspray
1.03 QUALITY ASSURANCE
A. Installer's Qualifications: Installation of Therma-Floor “Green” 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 Therma-Floor “Green”,
building interior shall be enclosed and maintained at a temperature above 50 degrees F (10
degrees C) and below 100 degrees F (37.7 degrees C) until structure and subfloor temperature
PART 2 PRODUCTS
A. Therma-Floor “Green” gypsum cement: Floor underlayment compound shall be
Therma-Floor “Green” gypsum cement underlayment 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. Subfloor Primer: Maxxon Floor Primer
E. Sealer: Maxxon Overspray
2.02 MIX DESIGNS
A. General Requirements: Therma-Floor “Green” mix proportions and methods shall be in strict
accordance with product manufacturer recommendations.
PART 3 EXECUTION
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 arrival of
the Therma-Floor “Green” underlayment crew.
B. Leak Prevention: Fill cracks and voids with a quick setting caulk or patching material where
leakage of Therma-Floor “Green” could occur.
C. Priming Subfloor: Prime subfloor using the Maxxon Floor Primer. Priming instructions vary
according to the porosity of the subfloor, multiple coats may be necessary.
D. Expansion Joints: Allow joints to continue through the Therma-Floor “Green” at the same width.
3.02 APPLICATION OF SELF-LEVELING FLOORING
A. Scheduling: Application of Therma-Floor “Green” shall not begin until the building is enclosed,
including roof, windows, doors, and other fenestration. Install after drywall installation unless
tenant finish requirements identify partitioning after the pour.
B. Application: Therma-Floor “Green” mix portions and methods shall be in strict accordance with
product manufacturer recommendations.
C. Drying: General Contractor shall provide continuous ventilation and adequate heat to rapidly
remove moisture from the area until the Therma-Floor “Green” is dry. General Contractor shall
provide mechanical ventilation if necessary. Under the above conditions, for 3/4 inch (19 mm)
thick Therma-Floor “Green”, 5-7 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 5-7 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
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: Therma-Floor “Green” mix shall be tested for slump as it is 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 Therma-Floor “Green” 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.
A. Protection From Heavy Loads: During construction, place temporary wood planking over
Therma-Floor “Green” wherever it will be subject to heavy wheeled or concentrated loads.
END OF SECTION