An innovative new product that elevates gypsum concretes to an unprecedented level of rock-solid performance. FIRM-FILL® 3310 floor underlayment's fast-setting surface rapidly eliminates water allowing for accelerated drying time and unparalleled levels of strength and finish over wood and concrete subfloors in new construction and renovation projects.

• Multi-Family
• Custom Homes
• Commercial Buildings
• Hotels & Motels
• Renovation Projects

• Premium strength, smooth surface over wood and concrete subfloors
  
• Eliminates water rapidly for accelerated drying time
  
• FIRM-FILL® 3310 Floor Underlayment can be poured before or after drywall
  
• Exceptional compressive strengths from 2000 to 3300 psi
  
• Delivers fire resistance and improved sound performance
  
• FIRM-FILL® 3310 Floor Underlayment creates a smooth, crack-free surface
  
• Expert application; installed only by trained, Licensed Applicators
  
• Meets ASTM F2419, Standard Practice for the Installation of Thick Poured Gypsum Concrete Underlayments and the Preparation of the Surface to Receive Resilient Flooring

Technical Data	Properties	ASTM
Weight	7.6 psf at 3/4"	C-472
Thickness	3/4" (19mm) (minimum over wood) to 3 1/2" (89mm); 1/2" (13mm) (minimum over concrete)
Compressive Strength	2000 - 3300 psi	C-472
Thermal Performance	K-value of 2.8 Btu; R-value of 0.36 ft2.h.°F/Btu	C-177-76
Fire Hazard Classification	Flamespread index 0; Fuel Contribution 0; Smoke Density 0	E-84
Patty Size	7 1/2" (approx. 191mm) plus or minus 1/2" (13mm) in diameter
Sand	1/8" (3mm) or less washed plaster or masonry sand	E-11
UL Listings	Listed in over 83 1, 2, 3, and 4-hour floor/ceiling assemblies