Profile Selections


90 X 19mm

Kwila Decking


per LM inc GST


140 X 19mm

Kwila Decking


per LM inc GST

Kwila Hardwood Decking

Kwila (Instsia spp) is a South East Asian tropical hardwood, and it has become a very popular choice around New Zealand homes and a proven naturally durable product, this attractive gold to reddy-brown coloured timber will age to driftwood grey if left to weather. Kwila is hard wearing, easy to work with and has good strength, durability and excellent stability.

You can use this decking with either the smooth side up for a cleaner look, or the griptread side up for more grip in the wet. New kwila decks are susceptible to a reddy-brown tannin bleed in the first few months of being laid.

Key Features

  • Sizes 90x19mm and 140x19mm

  • Available in random lengths 1800-5100mm

  • Kwila will bleed tannins when first laid

  • Recommend stainless screw fixings

  • Factory coating service available

  • FSC certified is available

  • Naturally durable hardwood – chemical free

  • #1 selling hardwood decking in NZ!!

  • Ensure adequate ventilation around boards



Ventilation- free-air circulation under the decking is very important to help minimise cupping and warping. Proper ventilation ensures the potential difference in moisture content levels between top face and the underside of boards is reduced and extends the life and performance of the deck.

The sub deck should have at least 300mm clearance from the ground. This, in conjunction with suitable board spacing, will allow for adequate ventilation. In wet areas or over water, additional clearance is recommended. Other steps that can be taken to minimise moisture differential are – a ground level vapour barrier*(with slit drainage) and pre-coating the underside of the deck boards. Failure to provide for suitable ventilation is a major cause of early decking failure.

*Note: Using polythene sheet can create water pooling having the opposite effect.


  • Joist spacing 400-450mm recommended for 19mm thick decking.

  • Joists should be clean and sound and the screws should penetrate at least 40mm into the joists to achieve good holding.

  • Pre-drilling and counter-sinking is essential to avoid any splitting or ‘tear-out’ where the screw penetrates the Kwila.

  • Kwila hardwood decking should be spaced with 4mm min. gaps between decking boards. This will allow for some expansion & contraction as the decking boards acclimatise as well as allowing for drainage of surface water and good air circulation.

  • Note: These are recommendations only. An allowance for regional climatic conditions should also be factored in. Ask us for advice regarding your specific requirements!


To enhance stability, bleeding and Kwila’s natural beauty we recommend coating the decking boards either before or following installation.

Note: When coating decking timber, ensure that the boards are free from surface marks and stains before coating. End sealing will help minimise splitting and surface checking on the ends of the boards.


We strongly recommend use of stainless steel screws for fixing your decking to the deck frame. We recommend 60mm long stainless-steel screws through the pre-drilled face of a 19mm thick decking board, two screws per joist.


Maintenance Cleaning & Washing

Hardwood decks should be cleaned with a stiff brush at least once a year to clear gaps between your decking boards and remove dirt and grim. A stiff brush can also remove any surface mould which can be a slip hazard in wet weather. Keeping the deck clear of leaf litter, moving pot plants and other large objects that may hold moisture to the top of the deck, is also important for the life of the deck. Hardwood Decking can be water blasted BUT it is important to do so at a low pressure so you do not damage the fibers of the timber.

Preparation for re-coating: Removing dirt and mould prior to coating is easy with OneStopDeckShop Deck Clean, a simple 4 step system that ensures your deck is ready for re-coating. OneStopDeckShop Deck Clean active restoration agent is the recommended product for general cleaning. Follow the manufacturer’s instructions when using.

Re-coating. Always follow the manufacturer’s specification for re-coating. We can assist you with choosing the correct coating product for your job as there is a range of different products that are suited to various deck types.