FAQ

Yakisugi (焼杉, lit. “burnt ceder”) is fire-treated timber from the Japanese ceder
(Cryptomeria japonica, Japanese: Sugi). The term refers to a finished cladding material –
not a burning technique that can be applied to any wood. The heat treatment works not
only on the surface but transforms the entire board from the inside out, giving the timber
extraordinary resistance to weathering, fire, pests and UV radiation – without any
chemical wood preservatives.

No. Yakisugi refers exclusively to timber from the Japanese ceder that has been refined by fire. In Europe, domestic timbers such as larch or pine are frequently charred and marketed as “Shou Sugi Ban” – this is technically not Yakisugi, and whether the timber has actually been treated evenly and thoroughly with heat usually remains unclear. Japan also has larch, pine and Douglas fir – yet Japanese craftsmen deliberately choose ceder and ceder alone. The reason is straightforward: the Japanese ceder is naturally resin-free, dimensionally stable, particularly soft and lightweight, all of which makes even carbonisation and heat treatment possible in the first place. Anyone looking for authentic Yakisugi should check the species stated on the product data sheet.

cladding material made from Japanese ceder.

Yakisugi is a cladding material that has existed in western Japan since the 18th century. The Japanese ceder was used to clad rural buildings because it had to withstand the demands of the local climate: salt air, moisture, insect attack and fire risk. The charred surface offered all of this in one – without chemical additives. These same properties make Yakisugi particularly well suited to the European climate, from the damp Atlantic coast to the temperature extremes of central Europe.

Yakisugi’s durability comes not from the charred surface alone, but from the heat treatment of the entire board – inside and out. The heat permanently hardens and compresses the wood cells, meaning the timber absorbs significantly less moisture. This makes Yakisugi resistant to rot, mould and pests. Conventional timber cladding swells in wet conditions and contracts in dry ones – the heat treatment significantly reduces this expansion and contraction. This is also why Yakisugi, at 10–15 mm, is considerably slimmer than the European standard of 18–24 mm: the timber has already been fully treated and requires no additional thickness as a buffer. In Japan, façades with a service life of 60 to 80 years are by no means unusual – some even last over 100 years without any maintenance.

Yakisugi was originally used in the coastal regions of western Japan – a climate known for its high humidity, salt air and pronounced temperature swings. These very conditions make Yakisugi one of the most weather-resistant cladding materials available: the heat treatment protects against rot and reduces the timber’s expansion and contraction so significantly that it remains dimensionally stable even under extreme climatic variation. Yakisugi is therefore well suited to the European climate – whether on the damp Atlantic coast, in the snow-heavy Alpine regions, or in the continental climate of central Europe. UV radiation, frost and salt air all take a considerably smaller toll on Yakisugi than on conventional timber cladding or other façade materials.

In addition to the classic deep-black Suyaki surface, there are brushed variants that highlight the wood’s grain, as well as lighter greys or natural looks. Especially with once- or twice-brushed products, the choice of natural oils, stains, and pigments can create further attractive accents tailored to your project.

Nakamoto Forestry does not offer Yakisugi in tongue-and-groove, as this profile is prone to moisture damage. A thin charred tongue would also lack structural stability. Our rebated and square-edged profiles offer maximum durability and can be used for both interior and exterior applications. Read more in our Blog.

Newly produced Yakisugi can have a subtle smoky scent, typical of the charring process. This scent usually dissipates quickly and completely. For interiors, we recommend factory-finished surfaces and a short airing period before moving in.

Yes. Yakisugi is one of the most sustainable timber cladding systems on the market: the finishing process requires no chemicals, the material is biodegradable, and its exceptional longevity reduces the need for replacement or retreatment. Nakamoto Forestry manages over 2,000 hectares of its own forests in Japan according to sustainable forestry principles – for every tree felled, a new one is planted. Nakamoto Zourin has held PEFC/SGEC certification since 2004; Nakamoto Forestry Europe has held PEFC Chain of Custody certification since 2020.

Yakisugi offsets the carbon footprint of its transport through its exceptional longevity over its entire service life: a material that lasts decades without retreatment or replacement has a significantly better overall balance than shorter-lived alternatives. Sea freight from Japan is also more carbon-efficient than many overland transport routes within Europe. Finally, distribution and warehousing are handled in Germany (near Düsseldorf) – short delivery routes within Europe, with no intermediaries.

It is worth distinguishing between two things: the physical durability of the material and the appearance of the surface. Yakisugi is structurally sound for decades without any maintenance – retreatment is only truly necessary if you wish to preserve the original deep black colour. Without re-oiling, Yakisugi develops a silver-grey patina over time – an ageing process that is regarded in Japan not as a flaw, but as a natural beauty. This principle of embracing impermanence and the passage of time even has its own term in Japanese: Wabi-Sabi.

Nakamoto Forestry recommends pre-treating Yakisugi with our natural oils or stains to maintain consistent façade colour over time. The durability of the boards is ensured by the heat treatment, but the colour of untreated wood changes gradually under UV exposure. Since most customers want colour retention and soot binding, we recommend a pre-treatment coating.

Despite its durability and beauty, Shou Sugi Ban (Yakisugi) has some aspects that, if poorly understood, may be seen as disadvantages:

• Quality: The Yakisugi method requires experience and care. Only complete, correct heat treatment, as perfected by the Nakamoto family over decades, ensures a high-quality product that lasts for many decades.
• Maintenance: Although the surface is weather-resistant, occasional oiling may be required—particularly in areas with heavy wear or high UV exposure. During installation, care must be taken not to damage the char layer through strong pressure or impacts.
• Cost: Yakisugi façades are mid-range in purchase price. However, low maintenance and long service life make them cost-effective in the long run.

Note: Apparent disadvantages usually stem from poor advice or lack of product knowledge.

Yakisugi was originally developed exclusively as exterior cladding and used solely for façades for centuries. It was only with growing popularity in the West that the material began to be used indoors as well – a development that has since found its way back to Japan itself. Today, Yakisugi is used by architects worldwide, primarily for:

• Exterior façades (residential, commercial and hospitality projects)

• Interior cladding as a design feature

Its characteristic deep black finish with visible wood grain makes it a favoured material for projects where sustainability and aesthetics go hand in hand.

Yakisugi can be installed either horizontally or vertically. Both methods are common in Japan. It can also be installed diagonally to create a distinctive design.

Yakisugi is a rebated solid-wood cladding and is installed much like other timber façades, but requires careful handling of the charred surface.

Key steps:

• Prepare substructure—dry, load-bearing, and made from suitable weather-resistant materials.

• Use corrosion-resistant fixings—ideally stainless steel screws or concealed clips.

• Handle gently—avoid rubbing or damaging the carbonised layer.

• Plan for ventilation—ensures moisture regulation and extends service life.

• Protect cut edges—treat freshly cut areas with matching oil or by re-charring.

Our delivery and installation guidelines provide comprehensive advice on preparation, installation, and maintenance to ensure a long-lasting, visually perfect façade.

European craftsmen can install Yakisugi without any special prior experience. Our Yakisugi boards are solid-wood cladding or formwork boards that can be installed according to standard European carpentry practices.

Yakisugi can be used on listed buildings if the material, colour, and surface comply with heritage authority requirements. However, prior consultation with the relevant heritage authority is necessary, as each building may have specific requirements for materials.

Yes, Yakisugi can be treated with fire retardants. Nakamoto Forestry offers a fire-retardant coating option. Please enquire about the specific requirements of your project.

Samples may cup more than full-length boards because of their shorter length. Thanks to our traditional sawing and planing methods—optimised for longevity and dimensional stability—as well as the way the timber is dried, most boards will show only about 1–2 mm of cupping. To minimise cupping, we recommend using two fixings every 40 cm along the grain direction.

We do not offer authentic Yakisugi for flooring. Sugi (cypress) is too soft to be used as flooring or decking. For furniture, the suitability of Yakisugi depends on the intended use—we are happy to advise you.

The standard dimensions of our Yakisugi boards are: 3970 mm in length, 15 mm board thickness. They are available in two profile variants and in the following widths: 89 mm, 145 mm, 195 mm. (PDF Download)
If you require shorter boards, please contact us.

Making Yakisugi yourself requires a great deal of experience and strict adherence to temperatures, timings, and process steps. It is a holistic process that, in addition to burning, involves choosing the right timber species and grade, proper drying, and controlled quenching. The boards are not just superficially scorched but made durable by full heat treatment. We therefore recommend relying on Nakamoto Forestry’s six decades of expertise and quality standards if you want authentic Yakisugi. If you still wish to try, we recommend these steps: 

Use only cypress—its very light, soft wood is ideal for deep carbonisation and a durable char layer.

• Dry the timber completely to 10–14% residual moisture (takes several weeks).

• Use rebated or square-edged profiles (not tongue-and-groove).

• Choose boards approx. 10–15 mm thick.

• Char only the “left side” of the board (the side away from the heart).

• Use the traditional triangular chimney method (avoid weed burners/Bunsen burners) and char the board deeply—until you think you’ve nearly ruined it—then immediately quench gently with water.

• If desired, remove soot with a soft wire brush.

Watch the steps on youtube!

We do not have a strict minimum order quantity, but for small orders (under 20 m²) we charge a small-order surcharge. Processing such small orders is considerably more expensive for us due to relatively higher fixed costs and lower production efficiency. This surcharge allows us to maintain our generally attractive pricing.

Authentic Yakisugi (Shou Sugi Ban) is a unique and ecological timber product. Although Yakisugi is becoming increasingly well known, for many it still seems exotic and sooty, and the patina so highly valued in Japan is still unfamiliar to European taste. This natural product has its own aesthetic that enriches your property without chemicals. Make sure all your questions are answered in a thorough consultation so you can enjoy the beauty of Yakisugi for decades.

Yakisugi – also known as Shou Sugi Ban – is a traditional Japanese method in which the surface of Sugi (Japanese cypress) is carefully charred with fire. The boards are then cooled, brushed, and finished. This process greatly increases the durability of timber cladding. The carbonised layer improves weather resistance, deters insects, delays fire, and creates a striking texture. The result is long-lasting, characterful cladding without chemicals and with a distinctly Japanese aesthetic.

For maintaining Yakisugi, we use traditional blends of natural, eco-friendly, plant-based oils such as linseed oil or tung oil. These protect the charred surface and highlight its colour and texture while keeping the timber breathable.

Particularly suitable are:

• Linseed oil: penetrates well, dries reliably, and is very weather-resistant, often the first choice for exteriors.
• Tung oil: forms a somewhat harder, water-repellent surface and beautifully enhances the grain.
• Natural oil blends with resins or waxes: specially developed for charred surfaces, they increase longevity and preserve the look.

Important: Our oils are solvent-free and suitable for outdoor use. We avoid varnish or plastic-based products, as they impair the breathable qualities of the Yakisugi surface.

Yakisugi (Shou Sugi Ban) is made from Japanese cypress / Sugi (Cryptomeria japonica)—a lightweight, dimensionally stable softwood used for centuries for Yakisugi. Sugi chars deeply and evenly, forming a protective layer with sufficient cohesion without becoming brittle. Its low weight makes installation easier and reduces façade loads. The straight grain and typical knots, once brushed, create the characteristic look of each variant.

Nakamoto Forestry cannot supply custom dimensions, profiles, or other grades. We stock selected grading classes of consistently high quality. As an exception to the standard dimensions, we can provide shorter boards upon request.

The Yakisugi method does not seal wood in the conventional sense like varnish or plastic coatings. Instead, during the heat treatment a carbonised layer forms on the surface, which acts as a natural barrier, repelling water and insects. The wood remains vapour-permeable and can regulate moisture. For added protection, especially under heavy weathering, charred wood is often treated with natural oils to extend durability and enhance its appearance.

The Yakisugi method protects wood mainly through two positive effects: The carbonised layer created by controlled charring acts as a natural barrier—repelling water, deterring insects and fungi, and reducing UV damage. The second effect comes from the change in the wood’s cell structure: heat shrinks and closes the cells, so they absorb less moisture. This makes the wood resistant to rot, reduces swelling and shrinking (“breathing” of the wood), and helps prevent cracking over time.

Authentic Yakisugi timber can be obtained exclusively through Nakamoto Forestry Europe. The Nakamoto family business is the only supplier in Europe offering original Yakisugi made from Japanese cypress (Sugi).

Thanks to the traditional heat treatment, Yakisugi is extremely weather-resistant without requiring an additional protective coating. It effortlessly withstands the harshest conditions—moisture, rain, extreme heat, or snow. With good planning and installation, the wood remains intact for decades. Colour changes are normal and not a defect. Regular cleaning and targeted re-oiling maintain water repellency and appearance; sanding is unnecessary.

No, Yakisugi does not require regular maintenance to remain durable and intact. If you wish to preserve the colour long-term, we recommend a maintenance coat every 5 to 10 years under moderate weathering. Local scratches should be cleaned and spot-oiled/touched up.

Importing Yakisugi does not make it more expensive than other providers, as our lean distribution model without intermediaries keeps costs competitive. Compared to many alternatives available in Europe—often chemically treated larch—our Yakisugi has a lower ecological footprint despite being imported. The price reflects the craftsmanship involved and consistently high quality—an investment in a durable, climate-friendly product.

Yakisugi timber has a very long service life—up to 80 years or more. Comparable untreated softwood often needs heavy refurbishment or partial replacement after 10–25 years. Exposure and maintenance can shorten or extend both lifespans.

For transport, Yakisugi boards are bundled and palletised for forklift handling. We add edge protection and, depending on the variant, insert oil paper between boards. For environmental reasons, we avoid shrink-wrapping in plastic. The charred surface is robust but should be protected from mechanical impacts. To make unpacking easier, boards are bundled in fours, with a weight of around 12 kg, making them easy to carry.

Yes. For private customers, statutory guarantee rights under national and EU law apply; in project business (B2B), the contractually agreed defect remedies apply. An additional manufacturer’s warranty may be granted—if expressly stated in the offer or order confirmation—for defined properties. Prerequisites include proper storage, ventilated construction, ground clearance, correct stainless-steel fixings, and adherence to maintenance intervals.

Nakamoto Forestry Europe offers various sample boxes. They cost around €20 net and contain six different variants, delivered within a few days via DHL. Please order in our shop.

During individual consultations or for architects specifying materials, samples are also provided free of charge.

Yakisugi can be installed using conventional fixing systems. We recommend using colour-matched stainless steel façade screws, available from the Nakamoto Forestry Europe shop. Binding details are provided in our installation and technical data sheets.

Prices for Yakisugi timber at Nakamoto Forestry Europe range from €70 to €90 per square metre, depending on surface treatment and finish. During a detailed consultation, we can determine the exact price for your project.

Yakisugi wood is not significantly more expensive than comparable timber cladding. Considering its service life of up to 80 years and very low maintenance requirements, overall costs are often lower than with other timber façades.