Plycem SX20/20 (formerly Plycem Cemdeck) is specified and listed under CSI Division 3-03500 Cementitious Decks and Underlayment.
- UL & ULC classified for use in fire-rated construction (UL 723, Test for Surface Burning Characteristics of Building Materials; UL 790, Test Methods for Fire Tests of Roof Coverings; and UL 263, Fire Tests of Building Construction and Materials).
- UL & ULC tested against ASTM E84 and E136
- Zero flame spread and zero smoke development per ASTM E84.
- Non-combustible per ASTM E136; 1 and 2 hour fire-rated floor assemblies.
- Structurally span rated, with UL listed floor assemblies
- STC rated assemblies per ASTM E413
- IIM rated assemblies per ASTM E989
- Factory sealed against water penetration.
- Minimal dimensional changes in temperature & moisture variations
- No food value to insects / vermin
- 71% Portland cement
- 19% mineralized cellulose fibers (derived from recycled cardboard cartons)
- 9% water
- 1% bonding agents.
- Available in 4’ x 8’ sheets
- Thicknesses 3/4” and 1”.
Product Brochure & Submittal Sheets
Specification & Certification
Building Code approvals
The Plycem 25mm Structural Flooring described has been evaluated for use as floor sheathing to support gravity loads for interior residential use. The Structural Flooring is permitted under the IBC on Type V Construction and buildings constructed in accordance with the IRC. The Structural Flooring has been evaluated for strength, physical properties, surface burning characteristics and non-combustibility.
The Plycem 25 mm Structural Flooring evaluated is as a satisfactory alternative to the following codes and regulations:
- 2015, 2012 and 2009 International Building Code® (IBC)
- 2015, 2012 and 2009 International Residential Code® (IRC)
Physical / Mechanical Properties
Acoustic Performance (STC & IIM):
Fire-Rated Floor/Ceiling Assemblies (ASTM E-119)
The following examples are indicative of the fire-rated floor/ceiling assemblies which are available. Please contact us for more information.
NYC Dept of Buildings, Materials & Equipment, Acceptance Division:
- USAP recommends 8 diameter minimum x applicable length, corrosion resistant screws with self-countersinking heads and self-drilling ‘Tek’ points. The length of the fastener should be a minimum of 2x the board thickness.
- For attaching 20mm (3/4″) Plycem Cem-Deck boards to steel framing (20 – 12 gauge)
- Grabber Part No. HS8158JBWG2 (#8 x 1-5/8″)
- Hilti PWH SD Cement Board Screw, No. 00372760 (#8 x 1-5/8″)
- ITW Buildex S-12 ‘Rock On’ No. 2159500 (#8 x 1-5/8″)
- Pro Twist Cement Board Fasteners
- Screw Fastener Pull-Out Test Report
Compounds, Sealers & Stains