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Therma-Floor® Data Sheet Maxxon Green Mark


Maxxon® Corporation
920 Hamel Road
P.O. Box 253
Hamel, MN 55340
Phone: 1-800-356-7887 or (763) 478-9600
Fax: (763) 478-2431

Product Description:

Therma-Floor® is a gypsum underlayment designed to pour over hot water tubes or electric heating cables. It acts as the thermal mass for any radiant floor system. Therma-Floor encases the tubes or cables in crack resistant, noncombustible gypsum. Its special formula resists breakdown to 150ºF (66ºC). And because it's poured only 1-1/4" (32 mm) thick, the heating system is more responsive and more comfortable.

Now always a "green" building material, Therma-Floor is an ideal solution for sustainable building projects.

Technical Data:

Compressive Strength: Typical range of 2,000 to 3,000 psi (14 to 21 MPa)
'K' Factor: 4.96 Btu · in/(h­ · ft² · °F) (.7142 W/[m · °C])
Specific Heat: .224 Btu/(lb · ºF) at 85ºF
(.9385 kJ[kg · ºC] at 29.44ºC)
Weight: At 1-1/4", less than 12 lbs./sq.ft.
(At 32 mm, less than 58.7 kg/m²)
Dry Density: 115 lbs./ft³ (1840 kg/m³)
Point Loading: Typical loading of up to 2,500 pounds (1134 kg)
on a 1" (25 mm) diameter disc
Thermal Resistance at 1" Thickness: R-0.208
Surface Burning Characteristics: Flame spread: 0
Fuel contributed: 0
Smoke density: 0
VOC: GREENGUARD Gold Certified

'Green' Information:

Sample USGBC LEED Credit Areas*
Project Credit Category How Requirement is Fulfilled
Indoor Environmental Quality IEQ 3.2 Air Quality Before Occupancy

GREENGUARD Certified (Field testing MUST be completed prior to claiming credit)

IEQ 4.3 Low Emitting Materials: Floor System GREENGUARD Gold Certified
Materials & Resources MR 2 Construction Waste Management Recyclable packaging and shipping materials
MR 4 Recycled Content Fly Ash
MR 5 Local/Regional Materials Manufactured in Blue Rapids, KS 66411; Las Vegas, NV 89035; Camden, NJ 08103; Job site manufactured with local sand & water
Innovation & Design ID 1 Sound Control Enhanced living environment
* Credits may vary depending on project type and Maxxon products used.

Gyp-Crete 2000 is a GREENGUARD certified gypsum floor underlayment 

Therma-Floor is GREENGUARD and GREENGUARD Gold Certified.
For additional information on GREENGUARD from UL Environment, the USGBC, and Gyp-Crete 2000/3.2K's qualifications for earning LEED points, please see our "Go Green" page.

Code Listings:
  • ESR-2540
  • UL ER 8477-01
  • ESR-1153
  • ESR-1141
  • ESR-1774
  • HUD951i
  • GREENGUARD Certified
  • GREENGUARD Gold Certified