Treated Timber Price Explained: Costs, Types & Outdoor Durability
What Is Treated Timber?
Treated timber is wood that has been infused with preservatives to protect it from rot, insects, fungi, and moisture. It is commonly used for decking, fencing, landscaping, and structural outdoor applications.
Types of Timber Treatment
- Pressure-treated timber: Chemicals are forced deep into the wood.
- Vacuum-treated timber: Lighter treatment for indoor or covered use.
- Water-based treatment: Safer and more environmentally friendly.
- Oil-based treatment: Better moisture resistance but higher cost.
Treated Timber Prices Per Cubic Meter
| Treatment Type | Average Price (USD/m³) | Best Use | Expected Lifespan |
|---|---|---|---|
| Untreated Softwood | $250 – $400 | Indoor construction | 5–10 years |
| Pressure-Treated Softwood | $350 – $650 | Decking, fencing | 15–25 years |
| Heavy-Duty Treated Timber | $500 – $900 | Ground contact | 25–40 years |
| Treated Hardwood | $700 – $1200 | Outdoor structures | 30+ years |
Is Treated Timber Worth the Extra Cost?
Untreated Timber
Initial Cost: Lower
Maintenance: Frequent
Lifespan: 5–10 years outdoors
Best for: Indoor, dry applications
Treated Timber
Initial Cost: 20–50% higher
Maintenance: Minimal
Lifespan: 15–30+ years outdoors
Best for: Outdoor, humid applications
Yes. Although treated timber costs more upfront, it significantly reduces maintenance, replacement, and repair costs. For outdoor projects, treated timber often delivers better long-term value.
Treated vs Untreated Timber Price Comparison
Treated timber usually costs 20–50% more than untreated wood. However, untreated timber used outdoors often fails early, making treated timber the more economical choice over time.
Frequently Asked Questions
Modern treated timber is safe when used according to manufacturer guidelines. Older treatments containing arsenic (CCA) have been phased out in most residential applications. Today's pressure-treated lumber uses safer chemicals like alkaline copper quaternary (ACQ) or copper azole. Always wear a mask when cutting treated wood and wash hands after handling.
Yes, but allow it to dry fully before painting or staining. Freshly treated lumber contains moisture from the treatment process. Wait at least 30-60 days for the wood to acclimate and dry. Use acrylic latex or oil-based paints/stains specifically formulated for pressure-treated wood. Proper surface preparation (cleaning, sanding) ensures better paint adhesion.
Periodic sealing increases lifespan, especially outdoors. While treated timber resists rot, it's still susceptible to weathering, checking, and splitting. Apply a water-repellent sealant annually to maintain appearance and performance. Check for signs of wear, clean regularly, and reapply finishes as needed to extend service life significantly.
Pressure treatment protection lasts 20-40 years depending on wood type and environmental conditions. Ground-contact rated lumber has deeper treatment penetration. The preservatives remain effective even if the surface weathers. For maximum longevity, ensure proper installation with adequate drainage and avoid ground contact where possible.
No, treatment levels vary. Look for stamps indicating retention levels: "Above Ground" (0.25 lbs/ft³), "Ground Contact" (0.40 lbs/ft³), or "Marine Use" (highest). Different wood species absorb treatments differently - pine accepts treatment well while some hardwoods require incising. Always choose the appropriate treatment level for your specific application.
Conclusion
This treated timber price guide shows why treated wood is essential for outdoor and structural projects. While it costs more than untreated timber, its durability and lifespan make it a smart long-term investment.