What is Accoya® Wood?
Accoya® is a high-performance modified timber engineered to overcome many of the limitations traditionally associated with wood.
Through a process called acetylation, the cellular structure of the timber is modified to significantly reduce its ability to absorb water. The result is a timber with exceptional dimensional stability, durability and resistance to rot — while retaining the natural appearance, workability and versatility of real wood.
Made from sustainably sourced timber, Accoya is suited to demanding exterior applications including windows, doors, decking, cladding, screens, pergolas and bespoke architectural joinery.
How Acetylation Works
Wood naturally contains hydroxyl groups that attract and release moisture as humidity and environmental conditions change. This continuous absorption and release of water is what causes conventional timber to swell, shrink, warp and move.
Accoya undergoes a controlled acetylation process that modifies these moisture-attracting groups within the wood. By significantly reducing the timber's ability to absorb water, acetylation improves both its dimensional stability and biological durability.
Importantly, the process does not impregnate the timber with toxic preservatives. The wood remains non-toxic, recyclable and suitable for a wide range of residential, commercial and architectural applications.
Performance You Can Design Around
Exceptional Stability
Accoya experiences approximately 80% less swelling and shrinkage than untreated wood. For architects, manufacturers and homeowners, this means greater design freedom and fewer of the movement-related problems traditionally associated with exterior timber.
- Significantly reduced swelling and shrinkage
- Reduced risk of warping, twisting and distortion
- Suitable for wide boards and large-format joinery
- Improved dimensional consistency in changing climates
- Helps coatings and finishes perform for longer
Built for Long-Term Durability
Accoya achieves the highest durability classification for timber and has been extensively tested in demanding environments around the world. Long-term real-world testing has also demonstrated a service life of 60 years and beyond.
- 50-Year Warranty — Above Ground
- 25-Year Warranty — In Ground or Fresh Water
- Particularly well suited to exterior applications where durability and longevity matter
Naturally Timber. Technically Better.
Despite its enhanced performance, Accoya remains real wood. It can be cut, machined, profiled, glued and finished using conventional woodworking equipment, allowing architects and joiners to create everything from traditional windows and doors to highly detailed contemporary joinery.
- Workable with conventional woodworking equipment
- Can be left natural to weather over time
- Stained to enhance the grain, or coated in virtually any colour
Designed with Sustainability in Mind
Accoya combines the renewable nature of timber with exceptional longevity. Because acetylation dramatically extends the usable life of the timber without relying on toxic wood preservatives, Accoya offers an alternative to many less sustainable materials traditionally used in demanding exterior applications.
- FSC® certified timber
- Cradle to Cradle Certified® Gold
- Platinum for material health
- Non-toxic modification process
- Fully recyclable
- Long service life — supports lower whole-life material consumption
Applications Across the Build
Accoya's combination of stability, durability and workability gives architects considerable freedom in how timber can be incorporated into a building.
Precision Where Movement Matters
Windows
Windows are particularly sensitive to timber movement. Accoya's exceptional dimensional stability helps frames and opening systems maintain their tolerances through changing weather and humidity, reducing the risk of sticking, swelling and distortion. Its stability also makes Accoya particularly suitable for large-format windows and exposed external joinery.
Explore Accoya Windows
Crafted Entrances Built to Endure
Doors
Doors demand both beauty and resilience. Accoya's exceptional dimensional stability helps doors maintain their fit and finish through changing weather and humidity, reducing the risk of sticking, swelling and distortion. Its stability also makes Accoya particularly suitable for large-format doors, sliding systems and exposed external joinery.
Explore Accoya Doors
Timber Designed for the Outdoors
Decking
Decking is exposed to continuous changes in moisture, heat and weather. Accoya's reduced moisture absorption and exceptional stability minimise swelling, shrinkage and distortion, helping decking maintain a consistent surface over time. Its stability also allows for considered board widths and tighter tolerances while retaining the warmth and character of natural timber.
Available in Natural Accoya® and Grey Accoya®.
Explore Accoya Decking
Design Freedom Without Compromising Performance
Cladding
Accoya allows architects to use natural timber cladding with greater confidence. Its dimensional stability means boards experience significantly less movement as environmental conditions change, helping maintain clean architectural lines and supporting longer-lasting coating performance. Accoya can be specified in a variety of profiles, widths, textures and finishes — or left uncoated to weather naturally.
Explore Accoya Cladding
Beyond Conventional Windows & Doors
Screens, Pergolas & Architectural Joinery
Accoya's performance extends far beyond conventional windows and doors. Its stability and machinability make it particularly well suited to bespoke architectural applications.
- Screens and shutters
- Pergolas
- Gates
- Garage doors
- Exterior ceilings
- Architectural fins
- Benches and outdoor furniture
- Planters
- Bespoke exterior joinery
From Homes to Landmark Architecture
Accoya has been specified on residential, hospitality, commercial and landmark projects around the world. Its ability to combine the warmth and beauty of natural timber with exceptional durability and stability has expanded the possibilities for where and how wood can be used.
Across Africa, Accoya has been used for everything from luxury residential windows and doors to lodge decking, cladding, large-format sliding systems and bespoke architectural joinery.
Residential
Luxury residential windows and doors where stability and longevity are essential.
Hospitality & Lodges
Lodge decking, cladding and bespoke joinery built to perform in demanding climates.
Commercial & Landmark
Large-format sliding systems and landmark architectural statements across the continent.
Timber Supply, Technical Support & Manufacturing
Resolute Timbers supplies Accoya® throughout Southern Africa and into markets across the continent. Our experience extends beyond timber supply. Backed by decades of hands-on joinery and manufacturing knowledge, we assist architects, designers, builders and manufacturers with:
Whether you are specifying Accoya for a single entrance door or developing a complete architectural timber package, our team can help determine the most appropriate solution for the project.