KOWHAI: Accoya for exterior siding and decking

KOWHAI by reSAWN TIMBER co. features Accoya® wood. KOWHAI can be used for interior or exterior wall cladding and exterior decking.


KOWHAI by reSAWN TIMBER co. features Accoya® wood. KOWHAI can be used for interior or exterior wall cladding and exterior decking.  Accoya® wood is the result of decades of research and development that has brought together a long-established, extensively proven wood modification technique and leading-edge patented technology – acetylation to create a high performance wood, ideal for outdoor use and challenging applications. 

By significantly enhancing the durability and dimensional stability of fast-growing and abundantly available certified wood species, Accoya wood provides compelling environmental advantages over slow-growing hardwoods (which are often unsustainably sourced), woods treated with toxic preservative chemicals, and non-renewable carbon-intensive materials such as plastics, steel and concrete.

  • The Accoya wood patented modification process adds nothing to the wood that does not already naturally occur in it
  • Class 1 durability – facilitating a longer lifespan, improved carbon sequestration potential and lower lifetime material consumption versus other materials
  • Outstanding dimensional stability, resulting in lower maintenance frequency and therefore less coating over the lifetime of the product
  • Superior thermal insulation, providing energy conservation advantages when used for applications such as windows and doors
  • All Accoya wood is produced from well managed sustainable sources including FSC® and other regionally certified woods
  • Low carbon footprint: Accoya wood is an environmentally compatible substitute for carbon intensive materials
  • Environmentally compatible: 100% recyclable and reusable, naturally renewable
  • Rapidly renewable materials: use of abundantly available and fast-growing source species

Accoya wood has been tested over prolonged periods in all types of weathering conditions – above ground, below ground and even in water – and has been proven to withstand even the toughest of external environments. Not only is its durability proven, but it has also been shown to retain its appearance, requiring much less frequent maintenance than other wood species. This gives added reassurance to the manufacturers, architects, specifiers, builders and property owners who have chosen Accoya wood for a diverse range of projects. Accoya wood is also being tested for additional uses by leading independent institutes worldwide.

Contact us for reSAWN TIMBER co. specific EXTERIOR Installation Guidelines. The Accoya Exterior Installation Guidelines on this page are a supplement only.


Additional information


3 options for standard dimensions:
3/4" thick X 5-3/8" wide
3/4" thick X 7-3/8" wide
5/8" thick X 5-3/8" wide
Contact reSAWN for custom dimensions / trim details


6'-16' Random Lengths


standardly Tongue & Groove
available S4S, shiplap and custom profiles




UNFINISHED (meant to weather naturally in place)


EXTERIOR siding, INTERIOR cladding, Decking


FSC® certified