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Therma-Floor® Data Sheet Maxxon Green Mark

Therma-Floor Sweets


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.

Therma-Floor, an Eco-Friendly building product, 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])
*R-Value = depth of pour in inches divided by K-Factor
0.252 at depth of 1.25"
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
Environmental Quality EQ 2 Low Emitting Materials
  EQ 4 Indoor Air Quality Assessment
  EQ 9 Acoustic Performance
Materials & Resources MR 3 Building Product Disclosure and Optimization - Sourcing Raw Materials
* Credits may vary depending on project type and Maxxon products used.


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

Code Listings:
  • ESR-2540
  • ULEU.R8477
  • ESR-1153
  • ESR-1141
  • ESR-1774
  • HUD951i
  • GREENGUARD Certified
  • GREENGUARD Gold Certified