Burnt wood, treated using the Japanese Yakisugi technique, has become a highly valued option in contemporary architecture and design. It stands out for its durability, sustainability, and visual appeal. It is ideal for wooden facades and cladding that combine aesthetics and resistance.
This traditional method charcoalises the surface of the wood with fire. This creates a natural protective layer that improves its resistance to weathering, insects and moisture. Furthermore, as it does not require chemicals, Yakisugi burnt wood is considered an environmentally friendly solution. It is perfect for modern projects committed to the environment.
In this article, we show you three types of wood that are compatible with this technique: spruce, larch, and heat-treated (thermo-D). This will allow you to choose the best option depending on the climate and end use, whether it be for façades, fences, terraces, or interiors.
1- Burnt Spruce Wood
Fir (Piceaceae family) is a light, soft wood that is easy to work with and very common in construction. In its natural state, it has a low-medium density and light-coloured grain with pronounced knots.
Yakisugi fir: warm aesthetics and extra protection
When Yakisugi is applied, spruce retains its low density, making it easy to handle and install. It gains resistance to the elements thanks to the charred layer, which acts as a protective barrier. However, even with charring, it is important to remember that spruce has moderate dimensional stability. Like most conifers, it can experience shrinkage or swelling with changes in humidity.
Compared to denser options, burnt spruce wood has less stability. It tends to move a little more with humidity than larch or thermo-D. It works well on façades in temperate or dry climates, such as single-family homes or enclosures in areas with moderate humidity. It is also used indoors, on walls, ceilings, or fixed furniture, where it provides a modern, textured finish. However, it is not recommended for floors, terraces, or steps, which require a more resistant wood. In very humid climates, it requires frequent maintenance.
Its main advantage is the price: it is the most economical option of the three. It is easy to install and lightweight.
2- Burnt Larch Wood
Larch mainly comes from cold regions such as Siberia or the Alps. It is a high-density conifer with marked grain and a high resin content, which gives it natural resistance to moisture. It is known as ‘wood that does not warp’ when properly dried. It offers greater dimensional stability than spruce and better withstands variations in temperature and humidity.
In its slow-growing Siberian variety, developed in cold climates, the narrow rings increase density and mechanical strength. Its high resin content acts as a natural barrier against fungi and moisture. Slow, controlled drying prevents cracks or warping. This process can only be guaranteed by a specialised supplier. This level of quality and care means that it may be slightly more expensive. However, it ensures stable, resistant wood with a timeless aesthetic. It is ideal for projects seeking exclusivity and high performance.
Yakisugi larch: maximum weather resistance
Historically, larch was used in shipbuilding and in structures exposed to water, such as bridges and piles. Its durability in outdoor conditions makes it a highly prized material. When Yakisugi is applied, burnt larch wood combines its natural strength with the benefits of carbonisation. In this process, the pores are sealed, water-sensitive compounds are removed, and its resistance to sun and moisture is reinforced. The result is a very stable wood that is ready for demanding outdoor projects.
Historically, larch has been used in shipbuilding and in structures exposed to water, such as bridges or posts. Its resistance to weathering makes it a highly valued material. When Yakisugi is applied, burnt larch wood combines its natural strength with the advantages of carbonisation. In this process, the pores are sealed, water-sensitive compounds are eliminated, and resistance to sun and moisture is enhanced. The result is a very stable wood that is ready for demanding outdoor projects.
Furthermore, as larch is a denser wood, it has greater structural strength. In a context of climate change, where wood can shrink or expand more frequently, it is essential to use robust fastening methods. Therefore, the only recommended system for burnt larch wood is installation with two stainless steel screws. They should be fastened directly to the front of the board, with a maximum spacing of 60 cm between them. This method ensures a firm and durable hold. This prevents unwanted movement over time.
3- Thermo-D Wood
Thermally treated wood, commercially known as Termo-D, is wood that has been modified using a chemical-free heat and steam process. It is subjected to temperatures close to 212 °C in the absence of oxygen, transforming its internal structure and drastically reducing its moisture content. The result is a darker, dimensionally stable wood with high resistance to rot and no resin exudation.
Its advantages are remarkable: it combines durability, stability and lightness in a single piece. It adapts to any climate and does not require constant maintenance. It is environmentally friendly, as it prolongs the useful life of fast-growing woods without the use of chemicals. The treatment affects the entire section, so even when cut or planed, it retains its properties and uniform colour. After planing, the surface is smooth and resin-free, ideal for both outdoor and damp indoor areas such as bathrooms, spas, or saunas.
Termo-D Yakisugi: unrivalled dimensional stability
In the market, thermo-D wood occupies a middle ground in terms of price. It combines the best of spruce—lightness and ease of working—with larch, with its superior stability and durability. This makes it the option with the best balance between performance, aesthetics and cost, offering an excellent return on investment.
It is suitable for outdoor use with or without a Yakisugi finish, and at Zenwood we offer both versions. Even without Yakisugi, it effectively resists moisture, insects and warping. With Yakisugi, these qualities are taken to another level. The pores are sealed and weather resistance is increased. In addition, a visually striking finish is achieved.
Thanks to its superior dimensional stability, it is the best choice for climates with sudden changes in temperature and humidity, such as mountainous areas. It is no coincidence that it is by far our best-selling product in Andorra: it combines beauty, low maintenance and reliable performance in a single material.
Conclusion and recommendation: ¿Qual es la mejor madera?
In short, every piece of Yakisugi wood has its own strength.
Burnt spruce wood stands out for its lightness and ease of working. It has a dimensional stability of 12% —the lower this value, the less the wood moves—. This translates into a more uniform finish and fewer adjustments over time. It is the right choice for decorative projects that require regular maintenance.
Burnt larch wood offers the highest natural resistance to moisture, fungi and insects. It also stands out for its great hardness and robustness. However, its dimensional stability is somewhat lower (16%). It is perfect for demanding outdoor applications where biological resistance is key.
Thermo-D combines the best of both species: the lightness and workability of spruce with the durability of larch. It has unbeatable dimensional stability of 2%, making it virtually immune to temperature and humidity variations. This makes it the most reliable choice for climates with sudden changes, such as mountain areas.
At Zenwood we are specialists in burnt wood and we can advise you on how to keep your façade, flooring or interior looking beautiful and performing well for decades to come. Request your free sample set today. See for yourself the quality, texture and finish of each type of Yakisugi wood before you decide.
