MELYWOOD TANNIN-FREE MERBAU
Decking | Cladding | Pre-Planed Boards
FSC® Merbau with the tannins removed: Class 1 durable, termite resistant, no drips, 25-year warranty.
WHERE TO BUY
Melywood is a new program at Nova. Ask us about availability, pricing and samples.
What Is Melywood?
Merbau (Intsia bijuga), also known as Kwila or Ipil, is a Southeast Asian hardwood with a density around 750 kg/m³, coarse texture, straight to interlocked grain and a deep brown color. It is naturally rated Class 1 to 2 for durability against fungi, durable against termites, and suitable for Use Class 4 — in-ground and fresh-water contact. As a decking and cladding species it has one well-known drawback: the heartwood is loaded with tannins that leach out in the first rains, leaving brown streaks on concrete, stone, stucco and any light material below the boards.
Melywood is Merbau that has been run through a proprietary modification process at the Melywood mill in Gresik, Indonesia, that destroys the tannins in the wood fibers. Melywood states the treatment is done without chemicals and that the wood remains 100% natural. The tannin problem goes away, and what remains is the Merbau that builders in Europe and Australia have long valued: hard, dense, dimensionally stable and long-lived outdoors. Boards are kiln dried to 13% (±2%) before treatment.
All Melywood is sourced from FSC® (Forest Stewardship Council) managed forests, and the product carries a 25-year warranty from the manufacturer.
The Benefits of Melywood
No Tannin Drip
The Melywood process eliminates the tannin bleed that stains the materials around an untreated Merbau deck or facade. No more brown streaks on concrete, pavers or siding below.
Class 1 Durability
Rated Class 1 to 2 for resistance to fungi and Use Class 4 for in-ground contact, without added treatment. Melywood backs it with a 25-year warranty.
Dense Hardwood
At 750–800 kg/m³ Melywood is naturally very dense, so it stands up to abrasion from furniture and foot traffic far better than softwoods or thermally modified light species.
Termite Resistant
Merbau is durable against termites (Class D). The treatment adds protection, making Melywood a strong choice for warm, humid and coastal locations.
Almost Zero Movement
Very low shrinkage and swelling across seasons, so joints stay even and boards stay flat. Melywood describes it as remarkably stable, resistant to deformation and dimensional variation.
100% FSC® Certified
Exclusively from FSC managed forests in Indonesia. Natural, recyclable wood with a low environmental impact across its life cycle.
No Chemical Treatment
Melywood is treated without chemicals. Nothing to leach into soil or water, and safe to handle and work with standard tools.
Low Maintenance
No regular treatment required. Periodic cleaning with water is enough; apply a protective oil only if you want to hold the color.
Color and Weathering
Melywood comes out of treatment a dark brown. Under the sun's UV it moves to a medium brown, generally within two months of exposure, and left unfinished it will weather to a light silver-gray patina over time — the look many high-end designers ask for. To keep the brown tone, apply a UV-protective penetrating oil such as ExoShield Wood Stain after installation and refresh it every one to three years depending on exposure. The photo shows a new board beside one weathered for six months.
- Dark brown after treatment
- Medium brown after about two months in the sun
- Silver-gray patina if left unfinished
- Finish with ExoShield to hold the color
Applications
Decking
Nova stocks Melywood decking as a 5/4x6 S4S E4E board (25mm x 140mm). The smooth surface is splinter-free and comfortable barefoot, and the density resists the abrasion of chairs and tables. Melywood supports both invisible fixing and traditional face-screwing; Nova's ExoDek QuickClip hidden fastener lifts each board 1/8" off the joist for airflow. Rated load per the manufacturer's data sheet is 400 kg/m² at a standard 400mm (16") joist spacing.
Rainscreen Cladding & Siding
The 1x6 S4S E4E board (19mm x 140mm) is the cladding profile. With almost zero movement and no tannin bleed, it is a natural fit for open-joint rainscreen facades on the ExoClad QuickClip system, and it also installs conventionally with screws or nails. Weather, humidity and UV resistance make it suitable for coastal and wet climates.
Soffit, Ceilings, Screens & Fencing
The same boards serve for soffit and porch ceilings, privacy screens and fencing, and other exterior details where a dark, dense hardwood is wanted without the maintenance.
Pre-Planed Boards
Melywood is also produced as pre-planed stock with a minimum profile on two sides for custom millwork. Ask us about other profiles and custom manufacturing on a project basis.
Melywood Specifications
Commercial name: Melywood®
Species: Merbau (Intsia bijuga); also known as Kwila, Ipil, Moluccan Ironwood
Origin: Indonesia, FSC® certified forests
Process: Proprietary Melywood tannin-removal modification, treated without chemicals
Drying: Kiln dried to 13% (±2%) before treatment
Density: 750 kg/m³ (750–800 kg/m³ range)
Hardness: Hard
Color: Dark brown after treatment, weathering to medium brown then silver-gray
Grain: Straight or interlocked (slight interlock)
Texture: Coarse
Sapwood: Clearly demarcated
Movement: Low or null
Durability against fungi: Class 1 to 2 — very durable to durable (EN 350-2)
Termites: Class D — durable
Use class: Class 4 — in-ground or fresh-water contact (EN 335-1)
Treatability: Class 4 — not permeable
Maximum deck load: 400 kg/m² at 400mm joist centers
Surface: Smooth; anti-slip profile available on request
Fastening: Standard face-screw or invisible (hidden clip)
Warranty: 25 years from the manufacturer
Nova profiles:
5/4x6 S4S E4E (25mm x 140mm), FAS, mixed grain, kiln dried — decking
1x6 S4S E4E (19mm x 140mm), FAS, mixed grain, kiln dried — cladding, soffit, trim
Notes: Merbau has variable resistance to marine borers, so Melywood is not recommended submerged in salt water. Wood dust from any hardwood can irritate skin and airways; use dust protection when cutting. Store boards protected from rain and direct sun before installation.
Installation & Care
Melywood installs like any dense tropical hardwood. Pre-drill for face screws and use stainless steel fasteners, as with any dense tropical hardwood, to avoid snapped screws and corrosion staining. For hidden fastening, use ExoDek QuickClip on decking and ExoClad QuickClip on siding. Seal cut ends with ExoWax to slow end checking. Acclimate the boards on site, stacked and stickered off the ground, before installation.
Maintenance is minimal. Rinse or wash the surface periodically to clear dirt and debris. No regular chemical treatment is needed. If you want to keep the brown color rather than let it silver, apply ExoShield Wood Stain after installation and reapply as it wears.
Frequently Asked Questions
Is Melywood resistant to termites and insects?
Yes. Merbau is naturally durable against termites (Class D), and Melywood's treatment adds further protection, making it well suited to warm and humid regions.
What is the lifespan of a Melywood deck or facade?
Melywood warrants the product for 25 years. Properly installed, a Melywood deck or cladding can last several decades, even in harsh climates.
Does Melywood require regular maintenance?
No. It needs no regular treatment. Periodic cleaning with water is enough to maintain its appearance, and a protective oil is optional if you want to hold the color.
Is Melywood suitable near the sea or in wet climates?
Yes. It resists humidity, mold and termites and is a good choice for coastal and humid environments. It should not be used submerged in salt water because of marine borers.
Will Melywood stain my concrete or siding?
No. Untreated Merbau bleeds tannins; the Melywood process removes them, which is the whole point of the product.
Is Melywood a thermally modified wood?
No. Melywood is a tannin-removal modification, not heat treatment. The wood keeps Merbau's full density and hardness, unlike the lighter species that are usually heat treated.
Melywood at Nova
Melywood is a new program at Nova USA Wood. We are starting with the two S4S E4E profiles above and limited inventory. If you have a decking, rainscreen or exterior trim project where a dense, tannin-free hardwood fits, contact us for current availability, pricing and samples.
Related products from Nova:
Made in Indonesia From FSC® Merbau
Melywood is manufactured at the company's own mill in Gresik, East Java, Indonesia, from Merbau harvested exclusively in FSC® managed forests. Logs are sawn, kiln dried, treated and profiled in-house, and the company sells through distributors in Europe, the Middle East, Asia Pacific and North America. Nova is bringing Melywood to the North American market alongside our other responsibly sourced tropical hardwoods.
WHERE TO BUY
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