Timber
Pressure-Treated Pine
Softwood infused under pressure with preservative chemicals to resist rot and insect damage, the default choice for outdoor structural framing.
Best for
- Deck framing and joists
- Fence posts and rails
- Any structural outdoor timber in ground contact or exposed to weather
Avoid when
- Visible decking surfaces where appearance matters as much as strength — cedar or composite often looks better for longer
Check the rating, not just the label
'Pressure-treated' alone doesn't guarantee ground-contact suitability. Look for a specific ground-contact rating for posts and any timber within 15cm of soil; above-ground rated boards will rot faster if buried.
It needs to dry before finishing
Freshly treated lumber is often still wet from the treatment process. Let it dry for several weeks (or until it no longer beads water) before staining or painting, or the finish will fail early.
Put this into practice
- Deck and Fence Material CalculatorHow much timber does my deck or fence need?