Products
USG underlayments & sound mats
Knell installs USG Levelrock gypsum underlayments and sound attenuation mats, along with cementitious toppings and lightweight cellular concrete. Here is a sample of the products we place most often. We match the product to the assembly, the subfloor and the strength your project needs.
Levelrock gypsum underlayments
| Product | Best for | Compressive strength |
|---|---|---|
| Levelrock 2500 Series | Thin pours over plywood in single-family, multifamily and hotel construction | 2,000 – 3,000 psi |
| Levelrock 3500 Series | Higher-traffic wood-frame and light commercial areas | 3,500 – 4,500 psi |
| Levelrock 4500 Series | Smooth, hard surface over concrete slabs, precast plank and post-tensioned decks | 4,000 – 5,000 psi |
Levelrock sound attenuation mats
| Mat | Notes | Mat thickness | Min. underlayment |
|---|---|---|---|
| SAM-N12 | Slim mat for most subfloors | 1/8" | 3/4" |
| SAM-N12 Ultra | Slim and economical with strong IIC | 3/16" | 3/4" |
| SAM-N25 | Economical, with moisture-control backing | 1/4" | 1" |
| SAM-N25 Ultra | Moisture-control backing with strong IIC | 5/16" | 1" |
| SAM-N40 | Raises IIC and STC to meet or beat code | 3/8" | 1" |
| SAM-N40 Ultra | For demanding sound environments | 7/16" | 1" |
Toppings & self-leveling
Cementitious self-leveling underlayments and toppings for concrete slabs, picked for the thickness range and strength the floor needs.
Cellular concrete
Lightweight cellular concrete in Class II through IV densities for engineered fill, bridge approaches and void fill. Submittals provided for your engineer.
Need a data sheet?
Email us the product or assembly and we'll send current manufacturer data sheets and submittals.
Have a project out to bid? Send plans to Bids@knellconstruction.com or call (801) 274-1178.
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