Fibre Cement Weatherboard | Material Atlas

Board · 7.5–16 mm

Cementitious — indicative fig. M·25

Fire A1 Non-combustible Embodied carbon 0.50kgCO₂e/kg Low–medium Compressive 38-46MPa Structural Design life 30yr

Profiled fibre cement lap cladding (1290-1300 kg/m3) in 7.5-16mm thicknesses, deemed-to-comply non-combustible per NCC C1.9(e), BAL-LOW to BAL-FZ rated per AS 3959, with 25-year James Hardie warranty and 30-50 year service life

01 Physical

Density 1290-1300kg/m3

Specific gravity 1.29-1.30

Porosity 28-35%

Water absorption 34-36%

Hardness 40-60HV

UV resistance excellent

Chemical resistance good

pH tolerance Stable at pH 5-13; avoid sustained acid exposure (pH <5)pH

Surface roughness 1-80 (finish-dependent: smooth 1-3, fine texture 10-25, woodgrain/cedarmill 20-80)um Ra

02 Mechanical

Tensile strength 2-4MPa

Compressive strength 38-46MPa

Flexural strength 7.0-10.0MPa

Shear strength 4-6MPa

Poisson's ratio 0.2-0.25

Impact resistance 4-10 (thickness-dependent: 7.5mm ~4-5 J; 16mm ~8-10 J)J

Creep resistance good

03 Thermal

Thermal conductivity 0.137-0.153W/mK

Specific heat 780-990J/kgK

Thermal expansion 0.008-0.010mm/m/degC

04 Compliance & Fire First question

Combustibility class Non-combustible (deemed-to-comply)

Fire resistance level 30-120 (system-dependent)minutes

Ignition temp Not applicabledegC

Flame spread index 0

Smoke dev. index 2-7

Heat release rate Near zerokW/m2

05 Sustainability & Health

Embodied carbon 0.5-0.8kgCO2e/kg

Carbon footprint 4.9-7.8 (HardiePlank 7.5mm reference); 10.4-16.6 (Scyon Linea 16mm)kgCO2e/m2

Embodied energy 6-10MJ/kg

Water footprint 20-40L/kg

Recyclability 10-30%

Recycled content 0%

Renewable content 5-15%

Circular score 3/10

VOC emissions Negligibleug/m3

Toxicity rating low

LEED contribution 1-3points

06 Durability · Cost · Logistics

Expected lifespan 30-50years

Maintenance interval 6-12months

Warranty period 25years

Material cost (range) $20-75/m2 supply only. HardiePlank ~$20-30/m2, Scyon Linea ~$40-70/m2, Scyon Stria ~$50-75/m2m2

Material cost (per unit) 3.20-10.00AUD/LM

Lead time 1-4weeks

Lifecycle cost 150-200AUD/m2

Annual maintenance 1-3AUD/m2/year

Market availability Readily available

07 Assessment

Advantages

Deemed-to-comply non-combustible under NCC C1.9(e) — no AS 1530.1 testing required
Suitable for all BAL ratings (BAL-LOW through BAL-FZ) per AS 3959 — universal bushfire zone compliance
AS 1530.3 indices 0/0/0/2-7 — NCC Group Number 1 fire hazard classification (best rating)
30-50 year service life with 25-year James Hardie product warranty
Complete termite and rot immunity — inorganic cement matrix unaffected by wood-destroying organisms
Concealed fastening system — no exposed nail/screw heads for superior weather tightness
Multiple profile options (HardiePlank, Linea, Stria) for heritage through contemporary aesthetics
ColorPlus factory finish with 15-year colour warranty and ~700 standard colours available

Constraints

Weight 2.4-3.8 kg/LM — heavier than timber weatherboards (~1.5 kg/LM for 19mm pine), requiring robust framing
Supply cost $40-75/m2 for premium Scyon products — higher than vinyl cladding ($15-30/m2) or basic timber weatherboard
Crystalline silica dust hazard during cutting — mandatory water suppression or HEPA extraction per SafeWork Australia
Moisture-driven dimensional movement 1.265mm over panel length — requires expansion gaps and proper overlap detailing
Repainting required every 10-15 years for field-applied finishes; ColorPlus extends to 15+ years but at premium cost
Brittle material — can crack if over-driven fasteners crush board, or if framing movement exceeds material flexibility
Limited recycled content in standard James Hardie formulations
Heavier than vinyl or aluminium cladding — increases structural framing loads and handling requirements

08 Applications

A1 Residential external wall cladding Primary application — horizontal weatherboard cladding for detached houses, townhouses, and duplexes. Replaces traditional timber weatherboards with superior durability, fire performance, and maintenance characteristics.

A2 Bushfire-prone area cladding Suitable for all BAL ratings (BAL-LOW to BAL-FZ) per AS 3959:2018. Non-combustible classification eliminates need for additional fire treatment. Minimum 6mm for BAL-40.

A3 Heritage renovation Woodgrain texture profiles (HardiePlank cedarmill) replicate traditional timber weatherboard appearance for heritage-appropriate renovation without ongoing timber maintenance requirements.

A4 Medium-density residential Cladding for apartment buildings and mixed-use developments up to ~4 storeys. Non-combustible classification meets NCC requirements for multi-storey external walls.

A5 Contemporary architectural facades Scyon Linea (deep shadow lines) and Stria (bold horizontal grooves) provide distinctive contemporary aesthetics for design-focused residential and commercial projects.

A6 Coastal construction Termite-proof and rot-resistant — ideal for coastal environments with high humidity and salt exposure. Corrosion-resistant fixings required in coastal zones.

A7 Gable end and feature cladding Weatherboard profile for gable ends, accent walls, and upper-storey feature elements. Combines with other cladding types (brick veneer, render) for mixed-material facades.

09 Sources & Standards

Sources pending — citations for this material are not yet recorded. Verify all figures against manufacturer data and current standards before specifying.