- Species available: Yellow Balau (Bangkirai), Jatoba (Brazilian Cherry), Angelim — all naturally Durability Class 1, from UK stock.
- Service life: 40–60 years above ground — no preservative treatment ever required.
- Cost: Yellow Balau £65–£90/m² boards. Jatoba £75–£105/m² boards. Angelim — contact for pricing.
- Best choice: Yellow Balau for the best value hardwood — widest profile range (smooth, ribbed, dual ribbed), most widely specified in the UK. Jatoba for the premium residential specification.
- vs ThermoWood: Hardwood lasts longer (40–60 yrs vs 25–40 yrs) and is harder/denser. ThermoWood has better dimensional stability and secret fix profiles. Cost broadly comparable.
- Delivery: 7–14 days from UK stock. All FSC and PEFC certified.
Hardwood decking is the premium end of the UK decking market — and for good reason. Naturally Durability Class 1, requiring zero preservative treatment, and capable of lasting 40–60 years with minimal maintenance, tropical hardwood decking outlasts every softwood alternative including ThermoWood. For homeowners building a deck they genuinely want to last a lifetime, and for architects and developers specifying premium outdoor spaces, Yellow Balau, Jatoba, and Angelim represent the strongest long-term specification available. This guide covers all three species — what they are, how they compare, what they cost, and which profiles are available from UK stock in 2026.
Hardwood decking boards — the dense, tight grain and rich warm tones of tropical hardwood decking. Yellow Balau and Jatoba are both naturally Durability Class 1 and require no preservative treatment throughout their 40–60 year service life above ground.
Why Choose Hardwood Decking?
Tropical hardwood decking occupies a distinct position in the UK market — above ThermoWood and Siberian larch in service life and density, and with a natural durability that requires no chemical modification or treatment. The three species we stock are all naturally Durability Class 1 under BS EN 350 — the highest durability rating in the European standard, meaning they are classified as Very Durable in above-ground exterior applications throughout a 40–60 year service life.
The practical implication is the same as for ThermoWood and larch: the board purchase is essentially the complete cost of ownership. No annual oiling required for durability, no preservative treatment, no replacement within the building's lifetime. The hardwoods do additionally benefit from periodic oiling every 2–3 years to slow surface checking and maintain colour — but this is cosmetic maintenance, not structural, and the boards will perform for 40–60 years whether oiled or not.
All hardwood decking we supply is FSC and PEFC certified — sourced from sustainably managed forests. The FSC certification is increasingly required on commercial and residential projects where sustainability credentials form part of the specification.
Yellow Balau (Bangkirai) Decking — The Most Specified UK Hardwood
Yellow Balau — also known as Bangkirai, its Indonesian trade name — is the most widely specified tropical hardwood decking in the UK market. Botanically Shorea laevis, it grows in South East Asia and produces a dense, stable, golden-brown timber with a fine interlocked grain that gives it excellent natural slip resistance on textured profiles. Its combination of Durability Class 1 performance, competitive pricing, and wide profile availability makes it the default hardwood decking specification for UK residential and commercial projects.
Yellow Balau characteristics
- Durability class: Class 1 — Very Durable under BS EN 350
- Density: Approximately 870–1,050 kg/m³ — significantly denser than oak (700 kg/m³) and ThermoWood (430–490 kg/m³)
- Janka hardness: Approximately 1,000–1,100 lbf — highly resistant to surface wear and indentation
- Colour: Rich golden-yellow to medium brown, often with subtle pale streaking. Weathers to silver-grey untreated
- Surface checking: Moderate — more checking than ThermoWood, less than Douglas Fir. Oiling reduces checking significantly
- Service life: 40–60 years above ground, no treatment
Ribbed face for enhanced slip resistance — the standard specification for residential hardwood decking. The ribbed surface significantly reduces the slip risk when wet compared to smooth profiles. Two ribs per board face.
Deeper 25mm boards with dual ribbed face — maximum slip resistance and the most structural profile. Recommended for commercial applications, pool surrounds, and high-traffic residential decks. The additional depth gives excellent rigidity at 400mm joist centres.
Clean flat face — the contemporary specification where slip resistance is managed through other means (anti-slip strips, careful drainage design) or where the clean surface aesthetic is a priority. The same Durability Class 1 performance as ribbed profiles.
Yellow Balau and Bangkirai are identical species with different regional trade names. Yellow Balau is the international botanical trade name. Bangkirai is the Indonesian/Malaysian industry name. If you see either term in a specification or quote, they refer to the same timber with identical performance characteristics. There is no quality or grade difference between suppliers using one name versus the other.
Jatoba — Brazilian Cherry Decking
Jatoba (Hymenaea courbaril) — commonly known as Brazilian Cherry — is one of the hardest, most durable naturally occurring decking timbers available in the UK market. Its deep reddish-brown colour, exceptional density, and striking grain character make it the premium residential hardwood decking specification for projects where visual quality and longevity are the primary criteria.
Jatoba characteristics
- Durability class: Class 1 — Very Durable under BS EN 350
- Density: Approximately 910–1,060 kg/m³ — among the densest of all available UK decking timbers
- Janka hardness: Approximately 1,260 lbf — significantly harder than Balau and more than twice the hardness of European oak
- Colour: Rich salmon-red to deep reddish-brown with prominent darker grain streaking. One of the most visually distinctive decking species available. Weathers to silver-grey untreated
- Surface checking: Low to moderate — Jatoba's high density limits moisture-related surface movement
- Service life: 40–60 years above ground, no treatment
Smooth face profile — the clean surface allows the distinctive reddish-brown grain and colour of Jatoba to read clearly across the deck. Jatoba's natural density provides inherent surface grip even on a smooth profile. The premium residential hardwood specification. Face fix with A4 stainless steel decking screws.
Angelim Decking — Contact for Pricing
Angelim is a genus of South American hardwood that encompasses some of the most durable timber species available in the global market. Angelim Amargoso and Angelim Pedra — both available from our UK stock — are Class 1 durability with exceptional density and a bold, distinctive grain character that is immediately distinguishable from the more familiar tropical hardwoods.
Pricing for Angelim fluctuates more than the established hardwood lines — contact our team for current per-m² pricing and availability. Contact us for Angelim pricing.
Hardwood Decking Species Compared — 2026
| Species | Durability | Density | Board cost/m² | Colour | Profiles |
|---|---|---|---|---|---|
| Yellow Balau / Bangkirai | Class 1 | 870–1,050 kg/m³ | £65–£90 | Golden-yellow to medium brown | Smooth, ribbed, dual ribbed |
| Jatoba — Brazilian Cherry | Class 1 | 910–1,060 kg/m³ | £75–£105 | Deep reddish-brown — most distinctive | Smooth |
| Angelim | Class 1 | High | POA | Warm brown, bold grain | Smooth |
Hardwood vs ThermoWood vs Larch — Which to Choose?
| Hardwood (Balau) | ThermoWood | Siberian Larch | |
|---|---|---|---|
| Durability class | Class 1 — Very Durable | Class 2 — Durable | Class 3 — Moderately Durable |
| Service life | 40–60 years | 25–40 years | 20–30 years |
| Treatment needed | None | None | None |
| Dimensional stability | Good | Excellent — lowest movement | Good |
| Secret fix available | No | Yes — Brofix system | No |
| Board cost/m² | £65–£90 | £55–£85 | £45–£70 |
| Weight | Heavy — 870–1,050 kg/m³ | Light — 430–490 kg/m³ | Medium — 550–650 kg/m³ |
| Sustainability | FSC/PEFC certified | European sourced, FSC/PEFC | European sourced, FSC/PEFC |
Choose hardwood (Balau or Jatoba) when maximum service life is the priority — 40–60 years versus 25–40 for ThermoWood — or when the rich natural colour and grain character of tropical hardwood is the design intent. Choose ThermoWood when secret fix (no visible fixings) is important, when dimensional stability in variable UK weather is a priority, or when a lighter board weight makes installation easier. Both specifications will outlast any softwood deck and both require zero preservative treatment.
Installing Hardwood Decking — Key Points
Hardwood decking installation follows the same principles as any exterior timber decking but with several species-specific details that matter for long-term performance:
- Pre-drilling essential: All hardwoods must be pre-drilled before screwing — the density of Balau and Jatoba will split boards and shear screws without pre-drilling. Use a 4mm pilot drill for 5mm screws throughout
- A4 stainless fixings only: Standard steel or galvanised fixings will corrode within 2–3 years against the tannins in tropical hardwoods, leaving black rust stains at every fixing point. A4 stainless steel is the only correct specification — two screws per joist per board, countersunk flush
- Joist spacing: Maximum 400mm centres for 21mm boards. For the 25mm dual ribbed Balau, up to 450mm centres is acceptable. Never exceed manufacturer recommendations for the specific profile
- Board orientation: Heart side down — hardwood boards cup away from the heart side as they dry. Heart-side-down installation means boards curve upward at the edges (self-draining) rather than downward (pooling)
- Expansion gaps: Leave 5–6mm gaps between boards for hardwood. Tropical hardwoods move less than softwood but seasonal expansion and contraction still occurs — consistent gaps prevent board-to-board contact and buckling
- End grain sealing: Apply exterior wood oil or end grain sealer to all site-cut ends immediately after sawing. Hardwood end grain is the primary moisture entry point
- Ground clearance: Minimum 50mm clear air gap between the bottom of the joists and the ground or gravel below — essential for ventilation regardless of species
Yellow Balau at 870–1,050 kg/m³ weighs approximately twice as much as ThermoWood and significantly more than larch. A pallet of Balau boards is substantially heavier than an equivalent pallet of softwood. Plan delivery access carefully — a fully loaded pallet of hardwood decking for a 20m² deck weighs approximately 400–600kg. Ensure your delivery access can accommodate a hiab or pallet truck, and allow extra installation time versus softwood — the weight affects handling speed significantly.
Hardwood Decking Maintenance — What It Actually Needs
Hardwood decking maintenance is straightforward and genuinely low obligation — far less demanding than the annual oiling cycle required by softwood decking. The honest maintenance picture:
- Preservative treatment: Never required. Class 1 durability means no fungicide or biocide is needed at any point in the service life
- Cleaning: Every 1–2 years — stiff brush, dilute exterior wood cleaner, work along the board grain. Rinse thoroughly. Removes algae, surface deposits, and organic matter from board gaps. See our timber decking cleaning guide
- Oiling: Optional, every 2–3 years — slows the natural weathering from rich brown to silver-grey and reduces surface checking. Apply Koopmans Houtolie after cleaning when fully dry. If you prefer the natural silver-grey weathered appearance, no oiling is ever needed
- Fixing inspection: Every 5–10 years — check A4 stainless screws are tight. The high density of hardwood means fixings stay stable, but a periodic check is good practice
What is the best hardwood decking in the UK?
Yellow Balau (Bangkirai) is the most widely specified hardwood decking in the UK — Durability Class 1, £65–£90/m² boards, 40–60 year service life, available in smooth, ribbed and dual ribbed profiles. Jatoba (Brazilian Cherry) is the premium residential specification at £75–£105/m² with exceptional hardness and distinctive reddish-brown colour. Both require no preservative treatment.
How long does hardwood decking last in the UK?
40–60 years above ground with correct installation — A4 stainless fixings, ventilated subframe, 50mm minimum ground clearance. Yellow Balau, Jatoba and Angelim are all Durability Class 1 under BS EN 350 and require no preservative treatment throughout this service life.
Does hardwood decking need treating?
No — Durability Class 1 hardwood needs no preservative treatment above ground. Optional oiling every 2–3 years slows natural greying and reduces surface checking but has no effect on structural durability. The boards will last 40–60 years whether oiled or not.
What is the difference between Yellow Balau and Bangkirai?
Yellow Balau and Bangkirai are the same species — Shorea laevis. Bangkirai is the Indonesian trade name; Yellow Balau is the international botanical name. Identical timber, identical performance. No quality difference between suppliers using either name.
Is hardwood decking better than ThermoWood?
Both are excellent zero-maintenance specifications. Hardwood lasts longer (40–60 yrs vs 25–40 yrs) and is harder. ThermoWood has better dimensional stability and secret fix profiles for a clean deck face. Hardwood is heavier and requires pre-drilling. Cost is broadly comparable. Choose hardwood for maximum lifespan; choose ThermoWood for superior stability and hidden fix options.
Hardwood Decking — Balau, Jatoba & Angelim from UK Stock
We supply Yellow Balau, Jatoba and Angelim hardwood decking boards from UK stock. FSC and PEFC certified. Tell us your deck dimensions for a precise board quantity and quote — nationwide delivery in 7–14 days.