FIRM-FILL® CMD (Corrugated Metal Decking)
Designed for use in multi-family, commercial and institutional buildings with light-gauge steel framing and a corrugated steel deck, FIRM-FILL® CMD is a lightweight, high-strength gypsum concrete floor underlayment. Installed at 1" above the top of the flutes, FIRM-FILL® CMD reduces deadloads and thickness, significantly lowering costs.
Recommended For
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Corrugated Metal Decking Application / MarketMulti-family, commercial projects, & industrial buildings. |
Features & Benefits
- Lightweight solution for fast-track construction
- Ideal for multi-family and mid-rise commercial applications
- Economical solution to build higher, faster, and lighter
- Creates a smooth, flat, rock-solid surface for the installation of finished floor coverings
- UL listed for 1, 1-1/2, and 2-hour fire-resistance per UL G565, G568
- Quick drying; can be walked on in 90 minutes
- Expert application; installed only by trained, Licensed Applicators
External Resources

Technical Data |
Properties |
ASTM |
Weight | Minimum 12.8 lbs/ft2 (62.47 kg/m2) at 1-9/16" (40mm) | C472M |
Thickness | 1" (25mm) above the flutes | |
Compressive Strength | Minimum 3500 psi | C472M |
Fire Hazard Classification | Flamespread index 0; Fuel Contribution 0; Smoke Density 0 | E84 |
Patty Size | 8-1/2 (216mm) plus or minus 1/2” (13mm) in diameter | |
Sand | 1/8" (3mm) or less washed plaster or masonry sand | E11 |