Roof Sheathing

Available variants

2 SKUs · all share width 1219mm where applicable

Density 1–1.2 kg/dm³ · Flexural strength ≥ 7 N/mm²

Compliance & certifications

Test reports and assembly references available on request for AHJ submittal.

• ASTM C1186-08 — Type A, Grade I
• ISO 8336:2018 — Category A, Class 1, Level 1
• ASTM E-84 — Flame spread 0, smoke developed 0

Frequently asked questions

Common technical and specification questions for Roof Sheathing.

• What roof coverings can be installed over Plycem Roof Sheathing?+

  It supports waterproof roof coverings including asphalt shingles, asphalt-mantle systems (modified bitumen, SBS torch-down), and PVC single-ply membranes. The panel acts as the structural deck — the waterproofing layer above is selected by the roofing system designer for the specific climate and slope.

• When do I specify 14mm versus 17mm thickness?+

  14mm (9/16") is typical for residential roof decking with rafter spacing up to 24" on-center. 17mm (11/16") is specified for commercial decks, longer spans, or where heavier-grade roof coverings are anticipated. Both thicknesses share ASTM C1186 Type A Grade I classification and ASTM E-84 Class A fire performance.

• Can this panel be used for exterior facade applications?+

  Yes — Roof Sheathing is also approved for exterior facade with exposed-joint detail (open architectural reveal between panels). The panel is fastened to the structural framing and joints are left visible as a design feature. For closed-joint or monolithic facade finishes, specify Exterior Hidden Joint or Fibroxton instead.

• Is it suitable for high-humidity or coastal environments?+

  Yes. Fiber-cement composition (ASTM C1186 Type A) is dimensionally stable in humid and coastal conditions where wood-based sheathing can swell, delaminate, or rot. Long Beach warehouse stock has been specified for projects throughout coastal Southern California and the Bay Area.