Scyon Linea weatherboard: builder's product guide
Scyon Linea weatherboard specs, install rules, and site checks: 16 mm fibre cement, 150 or 180 mm face widths, BAL-29, RCS wet-cut compliance, end-coat seal.
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Scyon Linea is James Hardie’s 16 mm thick pre-primed fibre cement weatherboard, the volume premium FC weatherboard on Australian residential builds. It comes in two face widths (150 mm and 180 mm) at 4.2 m lengths, pre-primed for paint. The 16 mm thickness lets it carry tongue-and-groove end joints, which means butt joints can land off-stud. That joint detail is what distinguishes Linea from older 7-9 mm FC weatherboards.
Three install rules carry the warranty and the safety obligation:
- End-coat seal every cut end with James Hardie’s pre-formulated end-coat (or equivalent) before fitting.
- Wet-cut, score-and-snap, or fibre-cement shears only for cutting. Dry-power-cutting is a respirable crystalline silica (RCS) hazard and is restricted under model WHS regulations.
- AS/NZS 4200.2-compliant pliable wall wrap must be installed behind Linea (it is not a self-supporting wall).
See Scyon (overview) for the wider Scyon range. This article zooms into Linea-specific install and product detail.
Product specifications
Verified 2026-05-16 from the James Hardie Scyon Linea product page:
| Spec | 150 mm face | 180 mm face |
|---|---|---|
| Face width | 150 mm | 180 mm |
| Effective cover width | 120 mm | 150 mm |
| Thickness | 16 mm | 16 mm |
| Length | 4200 mm | 4200 mm |
| Weight (installed) | 31.2 kg/m² | 24.9 kg/m² |
| Surface | Smooth, pre-primed | Smooth, pre-primed |
| Warranty (substrate) | 25 years | 25 years |
| Provenance | Australian-made, GreenRate-certified | Australian-made, GreenRate-certified |
The 150 mm face weighs more per m² because the narrower board generates more overlap area for the same wall coverage.
BAL rating: Scyon Linea is rated for BAL-29 standard when installed per the James Hardie install guide; higher BAL ratings (BAL-40, BAL-FZ) require specific assembly details, additional fire-grade backing sheets, and approved sealant. Verify the BAL detail on the construction certificate before specifying.
Cutting and RCS compliance
Linea is fibre cement, which means cutting generates respirable crystalline silica (RCS). Model WHS regulations restrict dry power-cutting and require dust-control measures. James Hardie’s published cutting methods:
- Score-and-snap with a fibre-cement scoring knife (manual, no dust).
- Hand or guillotine fibre-cement shears (manual, no dust).
- Wet-cutting with a water-fed diamond blade (dust suppressed to compliant levels).
- Vacuum-attached power cutting with a HEPA-rated dust extractor connected to the saw (dust captured at source).
What is restricted: uncontrolled dry power-cutting (handheld circular saw with no extraction or water feed). See respirable crystalline silica and wet cutting for the wider compliance picture.
End-coat seal: the warranty trigger
Every site-cut end of a Linea board must be sealed with James Hardie end-coat (or a manufacturer-approved equivalent) before the board is fitted. Cut ends absorb moisture orders of magnitude faster than the factory primer, and an unsealed end is the most common cause of edge-swell, paint failure, and warranty rejection.
Process:
- Cut the board.
- Dry-wipe the cut edge clean.
- Apply end-coat with a small brush along the full thickness of the cut end.
- Let the end-coat tack-up per the can instructions (usually 10-15 minutes) before fitting.
This applies to every cut: butt joints, scribed ends, mitred corners, and any cut around a window or door reveal.
Fixing pattern
Studs at 450 mm or 600 mm centres are standard for Linea install. James Hardie’s authoritative fixing schedule (which the builder must follow to maintain the 25-year substrate warranty) covers:
- Fastener type: corrosion-rated nails or screws per the install guide; HDG for treated pine and external exposure, 304 stainless for coastal exposure (within 1-3 km of breaking surf).
- Fastener position: blind-nail through the top of each board into the stud, hidden by the overlap of the next board above. Avoids face-nailing.
- Edge distances: minimum from board edges per the install guide; over-driving the nail can split the FC face.
- End joints: the tongue-and-groove end joint allows butt joints between studs (off-stud); plain butt joints land on studs.
Refer to the current James Hardie Linea Installation Guide before each project. The fixing requirements have evolved over editions.
Wall wrap behind Linea
Linea is a rain-screen-style cladding, not a self-sealing skin. AS/NZS 4200.2:2017 and the James Hardie install guide both require a compliant pliable wall wrap behind it, typically with a W1 water resistance and an appropriate vapour permeance class for the climate zone.
In cool climates (zones 6-8), use a vapour-permeable wrap behind Linea to allow inward and outward drying. See foil sarking for the wider sarking selection.
Common builder issues
- Cut ends not sealed before fitting. The most common warranty rejection; visible as paint-line failure and edge swell within 1-2 years.
- Dry-cut on site without extraction. Both a warranty issue (residue on the face) and a WHS issue (RCS exposure). Switch to score-and-snap, shears, or wet-cut.
- Wrong fastener corrosion grade. Hot-dip-galvanised nails in coastal exposure rust through; stainless is needed within 1-3 km of surf.
- Face-nailing instead of blind-nailing. Face-nail penetrations into the bottom edge of an upper board are visible and create water entry points; the install guide is unambiguous on blind-nailing for Linea.
- Tongue-and-groove butt joints incorrectly installed. The tongue and groove only develop their water resistance when seated fully; gaps allow capillary water entry.
- Wall wrap omitted or incorrectly lapped. Linea relies on the wrap as the primary water barrier behind the rain-screen face.
- BAL-29 detail mis-specified on a BAL-40 site. Linea’s BAL-29 rating applies to the as-installed standard detail; higher BAL ratings need additional backing per AS 3959:2018.
What to ask the supplier
Confirm in writing at order time:
- Profile and width: 150 mm or 180 mm face (cover widths differ).
- Pack size and length consistency: 4.2 m lengths across the pack.
- Pre-primer freshness: confirm packs are recent (older stock can degrade in storage).
- Current Installation Guide version: the install guide PDF current at order date; archive it with the project records.
- End-coat included or quoted separately: most suppliers quote it as a line item.
- Delivery method: Linea is heavy and prone to face damage in transit; specify face-protected packs.
References
- James Hardie Scyon Linea Weatherboard product page (verified 2026-05-16)
- AS/NZS 2908.2:2000, Cellulose-cement products
- AS 3959:2018, Construction of buildings in bushfire-prone areas
Related
- Scyon: James Hardie’s engineered fibre cement range
- Fibre cement cladding
- Weatherboard cladding
- HardieFlex
See also
Last updated: 2026-05-16. Verified: 2026-05-16.