For the past century, the UK and European tradition of using wood as a building material has been overshadowed by brick and concrete construction. With architecture now focused on visual aesthetics and environmental sustainability, designers are shifting focus back to timber cladding.
In UK and Europe, we typically apply oils, varnishes, paints and other protective coatings to the wood. This creates an outer barrier that helps to protect the timber from changing moisture levels. These are highly effective but need to be reapplied on a regular basis in order to maintain weatherproofing. In Japan, they chose to char in place of applying a coating. The controlled burning of the wood draws out natural resins and leaves a layer of carbon on the surface. As an integral part of the timber, this weatherproofing system is long-lasting. It is often coated with an oil finish for added resilience.
Our charred larch cladding is a modern application of the ancient Japanese art of charring timber to provide a beautiful and long lasting timber cladding. The manufacturing process is detailed, accurate and dangerous; one that we have perfected…
Traditional techniques are used by us to offer uniqueness to each individual project. There are many finishes and textures we can provide for interior and exterior projects. From the traditional highly charred fragile looking to the sleek and contemporary finish; we provide them all. Do not limit your imagination or design inspiration.
Charred cladding shades and technology
Our charred larch light shades are created by running the timber through a second wire brushing process that removes all loose soot from the softer spring growth rings and leaves the late wood as contrasting burnt ridges. It is a topographical, textured surface that follows the wood grain, and goes through an additional hand-grading to achieve a consistent blend of heartwood and sapwood lot to lot. Light shades must have an oil pre-finish applied to prevent sooty fingerprints during installation, and we have traditional oil as well as water-based natural oil options.
Charred larch black shades is our most popular Charred cladding (brushed Shou Sugi Ban) surface for exterior applications. A single pass through the brush machine knocks down the heavy soot layer and leaves a smooth, silky look. The burnt fibre crevasse shadows are subtle, and dark charred cladding can either be installed without oil pre-finish, with a traditional oil pre-finish, or with a water-based oil pre-finish depending on the appearance or colour desired.
Deep char is the most traditional and easily recognisable of our charred cladding shades. It is also often referred to as “alligator skin” or “dragon skin” outside of Japan. The charred soot is water-repellent and also partially protecting from UV. Therefore, Deep Char has the best wood and colour longevity as well as maximum fire resistance. We apply oil prefinishes to have the soot layer fixated. This prevents soot from coming off when touched, but also reduces blemishes and makes installation easier. In Japan there are numerous houses with Deep Char products applied for 80+ years with little to no maintenance.
Other Siberian Larch Cladding Profiles
Wood type: | Siberian larch (Larix sibirica) |
Cladding treatment: | None |
Density: | In dry state approx. 628 kg m³ |
Lifespan: | Proven life expectancy of 50+ years |
Quality class: | A+, A, AB (A and B mixed) Grade and quality description (PDF) |
Humidity: | Dried up to approx 16-18% (+/- 2%) |
Purpose: | Outdoor use |
Other uses: | Decking, Cladding, fencing, joinery, flooring |
Dimensions (mm): | 20 x 95 / 120 / 145 mm |
Origin: | Sustainable forests of Northern Russia (Siberia) |
Available length: | From 2 to 4 m |
Appearance: | The wood come in a warm mix of colours, from light yellow brown through to golden browns with a strong grain, similar to pine. Depending on the grading, the boards may contain a few dark knots. |
Weathering: | When the boards weather, the color changes to beautifully consistent silver gray, which is highly desirable in many cladding projects. |
Insect attack: | Resistant |
Treatability class: | Resistant |
Movement class: | High (A 145mm board can vary 3-4mm over the year.) |
Impact resistance: | High |
Scratches and abrasion: | Resistant |
Fire treatment: | Possible by impregnation |
Working characteristics: | Good workability. Receives fixings satisfactorily. |
Extracts: | Siberian larch is more likely to contain resin than oil or tannin. The resin is fixed by firing and does not tend to bleed out. Larch is fairly consistent and non-reactive and, as such, becomes relatively evenly weatherproof. |
When to fix: | Ideally autumn / winter months. |
How to fix: | Face fixation with stainless steel ring thigh nails. Pre-drilling recommended. |
Siberian Larch wood is naturally durable (Class 3 according to BS EN 350-2) – and therefore ideal for outdoor purposes – due to a combination of factors:
- The chemical composition of the wood creates a high resistance to rot and decay, which makes Siberian Larch one of the hardest and most durable softwoods.
- High density – this means that it is more difficult for decaying organisms to penetrate the wood.
- Long lifespan – lifespan of approx. 50-100 years with correct detailing and general outdoor exposure. Better durability properties can only be achieved with Accoya wood.
The natural durability of Siberian Larch means that no treatment of the wood is required and any coatings applied are for aesthetic purposes only.
Due to the high percentage of heartwood (75-90%) and the minimal proportion of sapwood, Siberian Larch is an extremely dense timber, which is classified by BS EN 350-2 as approximately 630 kg / m3 with a moisture content of 18%. As such, it is not easily damaged, making it ideal for highly exposed elevations, or applications where there is a likelihood of damage such as bumps or scratches.
The extreme continental climate in Siberia (Russia) produces a high proportion of late wood, which provides enhanced dimensional stability and enables a smoother machine finish.
In addition, our Siberian Larch is kiln-dried to around 16-18% (+/- 2%), the optimal moisture content for outdoor use. This moisture level is retained until delivery on site, so your Siberian Larch wood can be installed immediately. The benefit of kiln drying Siberian Larch, as opposed to air drying it, is that the timber dries uniformly and therefore achieves optimum stability.
Improved dimensional stability performance can be achieved by using narrower widths, for example 120mm and 95mm.
Our Siberian larch decking, cladding and sawn timber are available in various lengths, from 2m up to 4m. The standard board dimension is approx. 150mm, as this is traditionally the most commonly produced width. However, we also offer a range of other widths: 95mm, 120mm and 145mm. The narrower board widths offer a number of advantages, including a wider choice of design options and improved dimensional stability. As an added benefit, narrower board widths are generally rated well beyond their specification.
Cladding is supplied per linear metre based on random stock lengths at the time of order picking. Other sizes may be available on request.
Siberian larch timber quick tips
Sort your lengths. Make sure you’ve set them all up. We recommend ordering 10% more to cover waste material.
Siberian larch is very hard and dense wood. Use professional equipment for best results.
We recommend using only high quality stainless steel screws to avoid corrosion and stains on the wood.
OSMO wood protection offers effective multiple protection against UV rays and harsh environmental conditions.