+675 323 3319 Enquiry
Untreated timber in the tropics is a meal for termites and borers and a sponge for rot. The right timber — treated to the correct level for where it will sit — lasts for decades. The wrong choice can fail in a couple of wet seasons.

What you'll need

Everything here is stocked across our branches.

Step by step

  1. 1

    Match the treatment level to where the timber sits

    Timber is treated to different levels for different exposure: inside and dry needs the least; framing needs protection against termites and borers; anything outdoors, in the ground, or exposed to weather needs a much higher treatment level. Using indoor-grade timber outside or in the ground is why posts rot off at the base. Ask the branch for the treatment level suited to the position.

  2. 2

    Choose hardwood where it earns its keep

    For decking, structural posts, and anything taking load or weather, a durable hardwood or a properly treated timber outlasts cheap softwood many times over. For non-structural indoor work, treated softwood or board products are fine and cheaper.

  3. 3

    Check the timber before you buy

    Look for straight, sound lengths — avoid bad splits, large loose knots, and any sign of existing borer holes or soft rotten patches. Store it flat and off the ground so it does not bow or pick up moisture.

  4. 4

    Protect cut ends and drilled holes

    Treatment does not always reach the core. When you cut or drill treated timber, coat the fresh cut with an end-grain preservative — that exposed end is exactly where rot and insects get in.

  5. 5

    Keep timber off the ground and let it breathe

    Ground contact is the fastest way to rot timber. Use posts rated for in-ground use (or better, galvanised post supports/stirrups that hold timber above the soil), and design so water drains and air moves around the timber.

Tips for the PNG climate

  • In-ground and outdoor timber must be the right treatment level — there is no shortcut. Under-treated posts rot off at the soil line within a few wet seasons.
  • Always seal the ends and holes you cut in treated timber; the treatment is thinnest right where you just exposed fresh wood.
  • Galvanised post stirrups that lift timber off the ground beat setting a post directly in the soil almost every time.
  • Buy straight, dry, borer-free lengths and store them flat off the ground — warped or damp timber only gets worse in the humidity.

Common questions

Can I use ordinary timber for outdoor posts?
No — outdoor and in-ground timber needs a high treatment level or a durable hardwood, or it rots and gets eaten quickly. Ask the branch for timber rated for the position.
How do I stop timber posts rotting at the base?
Use in-ground rated timber, or better, keep timber above the soil on a galvanised post stirrup so it never sits in wet ground.
Do I need to treat the ends I cut?
Yes. Coat fresh cuts and drilled holes with an end-grain preservative — the core is less protected than the surface, and cuts are where rot and borers start.

Ready to start?

Add what you need to an enquiry and choose your nearest branch. We confirm the price and what is in stock before you travel — fourteen branches in ten locations.

Browse products Find your branch

More in Building & trade