FIRM-FILL® 4010
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 4000 to 5200 psi.
Recommended For
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Concrete Toppings & Self-LevelersNew concrete & cracked or damaged concrete. |
Features & Benefits
- FIRM-FILL® 4010 floor underlayment has exceptional compressive strengths from 4000 to 5200 psi
- FIRM-FILL® 4010 floor underlayment is cost efficient
- Creates a smooth, flat, crack-resistant surface
- Rapid installation; up to 25,000 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
External Resources

Product Resources
Technical Data |
Properties |
ASTM |
Weight | 7.8 lbs/ft2 at 3/4" (19 mm) | C472M |
Thickness | Feather edge in transitions to 2" (51mm) | |
Compressive Strength | 4000 to 5200 psi | C472M |
Fire Hazard Classification | Flamespread index 0; Fuel Contribution 0; Smoke Density 0 | E84, E136 |
Patty Size | 7 1/2" (191mm) to 9” (229mm) plus or minus 1/2" (13mm) in diameter | |
Sand | 1/8" (3mm) or less washed plaster, masonry sand or silica sand | E11 |
UL listings | Listed in over 100 1, 2, 3 and 4 hour floor/ceiling assemblies |