FIRM-FILL® 4010 Floor Underlayment is designed for thin capping of concrete in new construction or over damaged concrete in renovation projects. FIRM-FILL® 4010 Floor Underlayment's high strength and superior bonding characteristics will provide concrete floors with new life and exceptional surface hardness, offering compressive strengths ranging from 3500 to 5500 psi.

• New concrete
• Cracked or damaged concrete

• FIRM-FILL® 4010 Floor Underlayment has exceptional compressive strengths from 3500 to 5500 psi
• FIRM-FILL® 4010 Floor Underlayment is cost efficient
• Creates a smooth, flat, crack-free surface
• Rapid installation; up to 40,000 square feet installed per day
• FIRM-FILL® 4010 Floor Underlayment requires no troweling
• Unique bonding capabilities
• Proven performance and durability
• Quick drying; can be walked on in 90 minutes
• Expert application; installed only by trained, Licensed Applicators

Technical Data	Properties	ASTM
Weight	7 psf at 3/4"	C-472
Thickness	Feather edge in transitions to 1-1/2" (26mm)
Compressive Strength	3500 - 5500 psi	C-472
Fire Hazard Classification	Flamespread index 0; Fuel Contribution 0; Smoke Density 0	E-84
Patty Size	7" (203mm) plus or minus 1/2" (13mm) in diameter
Sand	1/8" (3mm) or less washed plaster, masonry sand or silica sand	E-11
UL listings	Listed in over 83 1, 2, 3 and 4 hour floor/ceiling assemblies