The Gold Coast’s warm climate and leafy surrounds create the perfect environment for termites — even in homes built with treated timber. While treated timber adds important protection against termites, it isn’t fool proof. If not installed or maintained correctly, termites can still find a way in. In this article, we break down what treated timber actually does, what H2, H3 and H4 ratings mean, and why termite inspections are still essential for protecting your Gold Coast home.
Living on the Gold Coast means sun, surf — and unfortunately, a high risk of termites. If you’re building or renovating, you’ve likely asked: Does treated timber really stop termites? The answer is — it helps significantly, but only when used properly.
What Is Treated Timber?
Treated timber is timber that’s been infused with protective chemicals to guard against:
- Termite attack
- Borer activity
- Fungal decay
- Rot and moisture damage
It’s widely used across homes on the Gold Coast for everything from framing and decks to garden walls and outdoor features.
Understanding Timber Treatment Ratings: H2, H3 & H4
Timber in Australia is treated to specific Hazard Levels (H-levels) that determine where it can safely be used:
H2 – Inside, Dry Areas
- Use: Internal framing, roof voids, trusses.
- Protection: Only protects against termites, not moisture or decay.
- Treatment: Often with permethrin or bifenthrin.
- Note: Suitable only for dry, enclosed internal areas.
H3 – Outdoor Use Above Ground
- Use: Pergolas, cladding, balcony rails — timber exposed to weather but not touching soil.
- Protection: Guards against termites, fungi, and decay.
- Treatment: Includes LOSP, copper azole, and ACQ.
- Note: Requires good ventilation and runoff. Can fail if timber remains damp.
- Use: Retaining walls, landscaping timbers, fence posts.
- Protection: Designed for direct soil contact, resisting decay and termites.
- Treatment: Typically CCA or ACQ, both strong copper-based preservatives.
- Note: Must be correctly installed with drainage to avoid long-term saturation.
The following video from the New South Wales Environmental Protection Authority explains the different treated timbers available in detail: NSW Environment Protection Authority
https://www.youtube.com/watch?v=M716uK3_jPU
⚠️ Where Treated Timber Can Fail
Even if your timber is treated, it’s not invincible — we see this often on the Gold Coast. Common problems include:
- Unsealed off-cuts or saw cuts exposing untreated core.
- Drilled holes not sealed after electrical or plumbing installations.
- Wrong rating used for the job — such as using H3 timber underground instead of H4.
- Timber buried in soil without proper clearance or protection.
🛠️ If you trim or drill into treated timber, always seal the exposed surfaces with an approved preservative to prevent termite entry.
🏡 Where Treated Timber Is Commonly Used:
- Framing and structural timbers
- Decking, external stairs, and posts
- Retaining walls and garden structures
- Outdoor furniture and timber features
🐜 Protect Your Home — Don’t Rely on Treatment Timber Alone
Treated timber is a fantastic line of defence, but termites can still bridge over or bypass it — especially in coastal climates with high humidity and lush gardens. That’s why regular termite inspections remain critical.
At Conquer Termites Gold Coast, we inspect hundreds of homes every year — and we know exactly where to look. Book an inspection today and make sure your home stays protected for the long term.
Call us on 1300 417 007
For more information:
https://www.conquertermites.com.au/articles/2024-12-27-what-types-of-timber-do-termites-eat-protect-your-home-from-termite-damage/
https://www.business.qld.gov.au/industries/building-property-development/building-construction/laws-codes-standards/using-timber/treated
