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GYP-SPAN® Radiant

GYP-SPAN® Radiant

Green Building ProductGYP-SPAN® Radiant is a gypsum concrete floor underlayment designed specifically for use over radiant heating systems. It encases the hot water tubes or electrical cables without air bubbles, creating a superior thermal mass that provides uniform heat transfer. GYP-SPAN® Radiant floor underlayment is the energy efficient and cost-effective way to create a smooth, flat, evenly heated floor surface for the attachment of virtually any finished floor covering.


Recommended For


Features & Benefits

  • Provides superior thermal mass for uniform heat transfer
  • Adheres to tubes or cables without air bubbles, dries without shrinkage cracks
  • GYP-SPAN® Radiant floor underlayment helps seal room perimeter for increased energy efficiency
  • Creates smooth, flat surface for the installation of finished floor goods
  • Used in "Green" construction
  • Quick drying; can be walked on in 90 minutes
  • Expert application; installed only by trained, Licensed Applicators
  • GYP-SPAN® Radiant floor underlayment has approvals from ICC-ES 4147 and HUD


Product Resources

Key: Word PDF Web Page
Product Submittal
3-Part Specifications
Project References
Drying Conditions Flyer
Post-Pour Instructions
Guidelines for Finished Floor Coverings

Featured Application

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Technical Data
Weight 14.6 lbs/ft2 at 1-1/2" (38mm) C472M
Thickness 1-1/2" (38mm)  
Compressive Strength 2000 - 3200 psi C472M
Thermal Performance K-value of 4.35 Btu/ft2·h·°F; R-value of 0.23 ft2·h·°F/Btu C177
Fire Hazard Classification Flamespread index 0; Fuel Contribution 0; Smoke Density 0 E84
Patty Size 7 1/2" (191mm) plus or minus 1/2" (13mm) in diameter  
Sand 1/8" (3mm) or less washed plaster or masonry sand E11
UL listings Listed in over 100 1, 2, 3 and 4 hour floor/ceiling assemblies