MATERIAL DATA SHEET

Acetylated Wood (Accoya), various profiles (19mm, 25mm, 32mm, 38mm, 50mm)

Millwork
organic › Timber › Millwork
organictimbermillworkacetylated-woodaccoyamodified-timberradiata-pineclass-1-durability50-year-warrantyfsc-certifiednon-toxicdimensionally-stablecladdingwindowsdeckingmarinecradle-to-cradle
ATLAS CODE
ORG-TBR-MW-003
Acetylated Wood (Accoya), various profiles (19mm, 25mm, 32mm, 38mm, 50mm)
Category organic
Material Family Timber
Regulatory Status Class D (EN) / Class C (ASTM)
Density
512 (432-592 range) kg/m3
Carbon (A1-A5)
200-500 (process dependent, before biogenic offset) kg CO2-eq/m3
Fire Class
Class D (EN) / Class C (ASTM)
Lifespan
60+ years
Description

Accoya acetylated wood transforms fast-growing FSC-certified Radiata Pine (Pinus radiata) into a Class 1 durable timber through molecular-level chemical modification. The acetylation process replaces hydroxyl groups in wood cell walls with acetyl groups using acetic anhydride, reducing moisture absorption by approximately 80% and delivering exceptional dimensional stability (radial shrinkage 0.4%, tangential 0.8% wet to 65% RH — compared to 4.8%/7.6% for Douglas Fir). The result is a non-toxic, biocide-free material with tropical hardwood performance from sustainably sourced softwood, backed by an industry-leading 50-year above-ground and 25-year in-ground warranty. Available in multiple profiles from 19mm to 50mm for cladding, decking, windows, doors, and structural joinery.

Primary Sectors
[Residential][Commercial]
Typical Uses
  • External window and door frames
  • High-performance cladding systems
  • Marine and coastal construction
  • Premium decking and outdoor furniture
  • Structural millwork and joinery
  • Commercial and residential exteriors
  • Heritage restoration projects
  • Extreme climate applications
Recycled Content 0
Renewable Content 100
Recyclability 100
Embodied Carbon 200-500 (process dependent, before biogenic offset) kg CO2-eq/m3
Embodied Energy 1200-2000 MJ/m3
EPD Available Yes
Advantages
50-year above-ground and 25-year in-ground warrantyClass 1 durability (EN 350) — surpasses Teak and Ironbark for rot resistanceExceptional dimensional stability — 80% reduction in moisture uptake100% non-toxic — no biocides, no harmful chemicals, no toxic leachingFSC-certified sustainably sourced Radiata PineExcellent machinability — works like natural timberTermite resistant (AWPA E1 rating >=9)Suitable for marine/coastal applications including salt water splash zonesThrough-core modification — cut ends perform identically to facesAvailable in natural and Color Grey (through-core stain) finishes
Cautions
Premium pricing — significantly more expensive than untreated timber (quote-based in Australia)Imported product — manufactured in Netherlands, longer lead timesSoftwood base — Janka 4.1 kN, softer than Australian hardwoodsAcetic acid (vinegar) odour during initial weathering periodHigher embodied energy than untreated timber due to acetylation processRequires stainless steel or Accoya-approved fixingsFire rating Class D (EN) / Class C (ASTM) — combustible, may not meet BAL-29Limited to Radiata Pine base — no species selection options
TECHNICAL DATA: PERFORMANCE PROPERTIES ORG-TBR-MW-003
Density (Dry) 512 (432-592 range) kg/m3
Specific Gravity 0.51 (0.43-0.59 range)
Porosity 3-5 (EMC at 65% RH) %
Water Absorption 3-5 (EMC) %
Hardness 4.1 (side) / 6.6 (end) kN
UV Resistance Good (with coatings lasting 2-3x longer than on untreated wood)
Chemical Resistance Excellent
pH Tolerance 3-9 pH
Available Colors
Natural honey-blonde (untreated Accoya)Accoya Color Grey — through-core grey stain (rich grey tone throughout depth)Accoya Color Grey weathers to consistent silver without revealing different substrate colourAccepts all standard timber coatings, stains, and paints
Surface Finishes
Uncoated (will naturally grey/silver over time)Accoya Color Grey (factory-applied through-core stain)Opaque paint systems (last 2-3x longer on Accoya)Semi-transparent stainsClear oils (e.g., CUTEK, Sikkens)SiOO:X silicon-based weathering system compatible
Texture Options
Dressed/planed smoothSawn face (textured)Brushed finishCustom machined textures
Pattern Options
Shiplap cladding profilesTongue and grooveRhombus/diamond claddingBoard-on-boardCustom milled profiles
Compressive Strength 35-45 MPa
Tensile Strength 40-60 MPa
Flexural Strength 39-40 MPa
Elastic Modulus 8.8 GPa
Impact Resistance 25-40 J/m
Creep Resistance Excellent
Abrasion Resistance Good (softwood)
Thermal Conductivity 0.108-0.12 W/mK
Thermal Resistance 0.17-0.45 (thickness dependent) m2K/W
Specific Heat Capacity 1300-1600 J/kgK
Thermal Expansion 0.003-0.005 mm/mK
Ignition Temperature 280-350 degC
Sound Transmission Class (STC) 22-28 STC
Noise Reduction Coeff. (NRC) 0.05-0.15 NRC
Optical
Light Transmittance 0 %
Light Reflectance (LRV) 15-45 (finish dependent) %

Wood acetylation was first studied in the 1920s as a laboratory technique, but commercial viability proved elusive for decades due to cost and process control challenges. Accsys Technologies (originally Titan Wood) achieved the commercial breakthrough in the early 2000s, establishing their first production facility in Arnhem, Netherlands. The Accoya brand launched commercially in 2007, with production capacity expanding to meet growing global demand. The acetylation process was refined to deliver consistent quality at industrial scale — each batch is tested to ensure minimum acetyl content thresholds are met. Britton Timbers became the Australian authorised distributor, establishing national supply chains. Accoya Color Grey (through-core grey stain) was introduced as a pre-finished product addressing the demand for weathered timber aesthetics. A second manufacturing facility was established in Malaysia to serve Asia-Pacific markets.

SAFETY, ECOLOGY & INSTALLATION ORG-TBR-MW-003
Flame Spread Index Class C (ASTM E84) FSI
Smoke Developed Index 200-350 SDI
Combustibility Class Class D (EN) / Class C (ASTM)
Ignition Temperature 280-350 degC
Fire Resistance Rating 30-45 (thickness dependent) minutes
Heat Release Rate 180-300 kW/m2
Toxicity of Combustion Low
Embodied Carbon (A1-A3) 200-500 (process dependent, before biogenic offset) kg CO2-eq/m3
Embodied Energy 1200-2000 MJ/m3
Water Footprint 60-150 L/kg
EPD Available Yes
Recycled Content 0%
Renewable Content 100%
LEED Points 5-8 points
Circular Economy Score 7.5 /10
VOC Emissions <20 (cured) ug/m3
Skill Level Qualified carpenter
Crew Size 2-3 people
Installation Time 2-4 hours/10m2
Curing Time 0 hours
Temperature Range 0-40 degC
Humidity Range 20-95 % RH
Required Tools
Standard carpentry tools — works like natural timberCarbide-tipped saw blades (recommended for clean cuts)Pre-drilling equipment for fixingsStainless steel or Accoya-approved fixings onlyDust extraction system (standard timber dust precautions)Standard adhesives (PVA, polyurethane, epoxy all suitable)
Certifications Required
Carpentry trade certificate (CPC30220 or equivalent)Working at Heights (for cladding installation)No Accoya-specific certification required
Weather Limitations
Standard construction weather conditions applyCan be installed in wider weather window than untreated timber due to moisture resistanceProtect stored material from prolonged standing water (good practice, not critical)
COMMERCIAL, LOGISTICS & REGULATORY ORG-TBR-MW-003
Material Cost 150-300 (estimated, quote-based) AUD/m2
Installation Cost 35-65 AUD/m2
Annual Maintenance 1-3 AUD/m2/year
Lifecycle Cost (50yr) 150-350 AUD/m2
Market Availability Good — national distribution through Britton Timbers + regional stockists
Lead Time 14-56 days
Supply & Logistics
MOQ Project-dependent
Design Life 60+ years
Warranty Period 50 (above ground) / 25 (in-ground) years
Maintenance Interval 8-12 years
Service Temp Range -20 to 65 degC
Dimensional Stability 0.4 (radial) / 0.8 (tangential) % change
Certifications Held
FSC Chain of Custody — certified sustainably sourced Radiata PineAccsys Technologies quality testing — each batch verified for acetyl content50-year warranty backed by manufacturerFSC certification (FSC-C158498)EPD available (Accoya acetylated wood)Cradle to Cradle Gold certifiedBREEAM A+ ratedNon-toxic — no biocides, fungicides, or harmful chemicalsSafe for food contact applicationsSafe for playground equipment
Fire Code Compliance
EN 14915 — Fire Class D (standard)ASTM E84 — Class C (standard), treatable to Class A/BNCC — Combustible material, permitted for cladding per NCC Volume 1 & 2AS 3959 — Radiata Pine NOT listed in Appendix F for BAL-29; may require Performance Solution or fire-retardant treatment
Standards Compliance
NCC 2022 — Compliant as external cladding (combustible material provisions)NCC Part 3.5.4 / Part 7.5 — Timber wall claddingAS 1684 — Residential timber-framed constructionAS 3959 — NOT listed for BAL-29 (Radiata Pine); requires Performance Solution for bushfire areasASTM E84 — Surface burning characteristics (Class C)ASTM D143 — Small clear specimens of timber (Janka hardness testing)ASTM D2017 — Natural decay resistanceISO 21930 — Environmental product declarationsISO 4469 — Wood — shrinkage determinationISO 14040/14044 — Lifecycle assessmentEN 350 — Natural durability of solid wood (Class 1)EN 113 — Wood preservatives (durability testing method)EN 408 — Timber structures — structural timber testing (MOR/MOE)EN 14915 — Solid wood panelling and cladding (Fire Class D)EN 12667 — Thermal performance (lambda = 0.108-0.12 W/mK)

DISCLAIMER: This specification document is generated from the CLAD Materials Atlas Database. Information is for general guidance only and does not constitute professional engineering advice. Values are typical and may vary by batch, manufacturer, and production run. Verify suitability for specific project applications independently.

ID: ORG-TBR-MW-003 Schema: v3.0