Choosing the Right Decking Timber for New Zealand
Building a deck is a significant investment, and choosing the wrong timber species can mean costly repairs or premature replacement within a few years. New Zealand's variable climate — UV exposure, coastal salt air, wet winters — puts real demands on outdoor timber. This guide compares the three most popular hardwood decking choices available at Timberman to help you choose confidently.
Vitex
Vitex (also known as Pacific Teak or Vitex cofassus) has become one of the most popular decking timbers in New Zealand, and for good reason.
- Durability: Naturally durable Class 1–2. Highly resistant to rot, fungi, and insect attack without chemical treatment.
- Hardness: Very hard and dense — holds up well under heavy foot traffic and outdoor furniture.
- Oiling/Treatment: Vitex benefits from an initial oil application and periodic re-oiling (typically every 1–2 years) to maintain its warm, golden-brown colour. Left untreated, it will weather to a silver-grey patina — which many homeowners actually prefer.
- Pricing: Mid-to-premium range. Its longevity makes it excellent value over the life of the deck.
- Best for: Residential and coastal decks where longevity and a premium appearance are priorities.
Browse Timberman's Vitex decking range →
Kwila (Merbau)
Kwila (Merbau) is a tropical hardwood widely used across New Zealand and Australia for outdoor decking.
- Durability: Class 1–2 durability — excellent natural resistance to decay and insects.
- Hardness: Extremely hard. Highly scratch and dent resistant, making it ideal for high-traffic areas.
- Oiling/Treatment: Kwila contains natural tannins that bleed during early weathering — you'll notice reddish-brown staining on concrete or surrounding surfaces after rain. This reduces significantly after the first season. Regular oiling is recommended to slow the greying process.
- Pricing: Generally competitive with Vitex. Widely available in standard decking profiles.
- Best for: High-traffic decks, pool surrounds, and projects where extreme hardness is a priority.
Other Hardwood Options
Beyond Vitex and Kwila, other hardwood species worth considering include:
- Garapa (Brazilian Ash): A lighter-coloured option with good durability. Less tannin bleed than Kwila and a clean, pale gold appearance.
- Totara: A NZ native with excellent natural durability — beautiful but typically reserved for high-end or heritage projects due to availability and cost.
Quick Comparison Table
| Species | Durability Class | Hardness | Oiling Needed? | Tannin Bleed? |
|---|---|---|---|---|
| Vitex | Class 1–2 | High | Yes (optional) | Minimal |
| Kwila | Class 1–2 | Very High | Yes | Yes (early) |
| Garapa | Class 2 | High | Yes | Minimal |
Which Should You Choose?
For most NZ residential decks, Vitex is our top recommendation — it strikes the best balance of hardness, natural durability, and appearance. If your priority is maximum hardness for a very high-traffic deck, Kwila is a proven performer; just be prepared for some early tannin management.
Not sure what's right for your project? Browse our full decking range or get in touch with the team at Timberman — we're happy to talk through your options.