Kwila Product Information

What makes Kwila decking different from other decking timbers?
Kwila is a class 1 durable species, meaning it has the highest above-ground durability rating available. With proper installation, including adequate gapping and ventilation, Kwila can last over 40 years. Stability is another key advantage, as Kwila has low dimensional movement, reducing the risk of splitting, cupping, or twisting compared to other decking timbers.

What makes Kwila decking different from other decking timbers?
Kwila timber is a natural, renewable resource sourced from FSC-certified forests, offering sustainability and wellbeing benefits through biophilic design. It can be repurposed or decomposed naturally at the end of its life. Plastic composite decking, on the other hand, cannot be recycled once it reaches the end of its lifespan and is prone to higher temperatures under the sun, static electricity, and replacement if scratched.

How long does Kwila decking last?
Kwila decking has a class 1 durability rating, meaning it can last over 40 years when installed and maintained correctly. It is naturally resistant to termites and less prone to rot and decay compared to other decking timbers.

Does Kwila decking have a slip rating?
In its pre-oiled condition, SpecRite Kwila decking does not have a slip resistance rating. If slip resistance is required, such as for poolside areas, a specialised slip-resistant finish like Intergrain UltraDeck Slip should be applied.

Does Kwila timber bleed?
Yes, Kwila contains high tannin levels, which can leach when first exposed to moisture. This can cause staining on nearby surfaces. To reduce tannin bleeding, a thorough and regular hose-down during the initial days of installation can help. Products like Intergrain Ultraprep Tannin and Oil Remover can also accelerate the process.

Can Kwila be used in bushfire-prone areas?
Yes, Kwila is rated BAL 29, meaning it is suitable for use in bushfire-prone areas rated at Bushfire Attack Level (BAL) 29 or lower. However, it is important to check local building regulations for specific installation requirements.

Is SpecRite Kwila decking termite resistant?
Yes, Kwila timber is naturally resistant to termites, fungi, and dry wood borers, eliminating the need for chemical treatments.

Is Kwila a sustainable timber choice?
Historically, Kwila has been linked to deforestation and illegal logging, but SpecRite sources its Kwila from FSC 100% certified forests. The FSC certification ensures responsible forest management that supports biodiversity, climate resilience, workers’ rights, and sustainable practices.

Kwila Installation

Should I use screws or nails for Kwila decking installation?
Kwila decking should be fixed using hot-dipped galvanised or stainless steel screws, with two screws per joist. Pre-drilling and countersinking are recommended to prevent splitting and achieve the best finish. Stainless steel fixings are ideal for coastal or poolside applications.

Do I need to leave gaps between decking boards?
Yes, proper gapping and ventilation are essential for the longevity of your deck. Without sufficient ventilation, moisture can accumulate, leading to cupping, twisting, and splitting. Although Kwila is highly stable, poor installation can still lead to performance issues.

Does ‘pre-oiled’ mean I don’t need to oil my deck?
No, SpecRite’s Pre-Oiled Kwila Decking has been primed with Feast Watson® Industrial Timber Oil, but it still requires top coating with either a water-based or oil-based finish for long-term protection.

Kwila Care & Maintenance

How often should I oil my Kwila deck?
To maintain the natural beauty of your Kwila deck, regular deck oiling is required. The frequency depends on factors such as exposure to the elements and the oil product used. Fully exposed decks may require re-coating every 12 months, while partially covered decks may last up to 3 years. For those who prefer a natural greying look, maintenance is not necessary.

What oil should I use on my Kwila deck?
SpecRite Kwila is pre-oiled with Feast Watson® Industrial Timber Oil, which is compatible with most water-based and oil-based topcoats. For maintaining a natural appearance, a lightly pigmented oil like Feast Watson® Traditional Timber Oil is recommended. For long-lasting protection, Intergrain® UltraDeck Timber Oil is a great choice. If a deeper colour transformation is desired, Intergrain® UltraDeck Timber Stain can be used.

Can GL17 Kwila posts be used in-ground?
No, SpecRite GL17 posts are designed for above-ground use only. While Kwila has a class 1 durability rating above ground, its durability is class 3 when used in-ground, meaning it will last only 7-15 years. Additionally, ground contact can cause excessive swelling, which may weaken glue joints.

Troubleshooting

How can I remove tannin stains from my Kwila deck?
A diluted oxalic acid solution can be used to reduce tannin stains. Always follow safety guidelines when using chemical treatments. Over time, exposure to sunlight will also help fade tannin stains naturally.

What causes black marks on my Kwila decking?
Black blotches are often caused by iron stain, which occurs when metal comes into contact with tannins in the timber. Common sources include water run-off from iron roofs, metal objects left on the deck, construction debris, fertilisers, or trace iron in water. Iron stains do not damage the timber and can be removed with oxalic acid, scrubbing, or sanding. Identifying and eliminating the contamination source will prevent recurrence.

Edge of deck with step with garden lawn in background

Resources

Decking Calculator

How-To Articles

Why Kwila Timber

FAQs

Guides & Technical Documentation