Shou Sugi Ban is a traditional Japanese method of charring wood with fire to make it more durable and weatherproof. The striking black carbon layer that is formed helps the timber resist fire, vermin and moisture.
Even though it is more durable than non-charred timber, Shou Sugi Ban timber still requires maintenance throughout its life. Below we explore how to look after burnt timber cladding to preserve its appearance and structural integrity for longer.
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Any Timber Cladding that is Exposed to Direct or Indirect sun will Require Maintenance
While Shou Sugi Ban cladding is highly durable, it does require maintenance in order to preserve its appearance over time. Exposure to elements like sun, wind and rain can weather the carbon layer and cause changes in its appearance.
A small amount of weathering may create an attractive crackled texture to the timber, but in the long term the timber will require re-coating with oil to avoid the top layer hardening and flaking.
Re-coating with oil should typically be done every 1-3 years, but the exact recommendations depend on the timber species used. Not every type of wood is suitable for making Shou Sugi Ban.
The art of Charring Timber – which Species work the Best?
Three of the most popular timber species used for Shou Sugi Ban in Australia are Burnt Ash, Jarrah and Spotted Gum. The density of the timber species affects how effective the charring process is.
Hard timbers like Spotted Gum take a long time to char and will warp if exposed to the fire for too long. However they can still be used for Shou Sugi Ban cladding – they will just have a thinner carbon layer. In other words, they will be less durable than timbers which char more effectively.
Slightly softer timbers like Burnt Ash are quick to char and will form a thicker carbon layer. This makes them more durable and long lasting. Plus, they will require less maintenance over time.
Very soft timbers such as pine are not used for Shou Sugi Ban because they char much too quickly. In these cases the wood becomes brittle and the charred layer breaks off.
Maintaining Shou Sugi Ban Cladding is not Hard
If you’re investing in burnt timber cladding for your home or commercial project, you’ll want to know: how long does Shou Sugi Ban last? And what maintenance does it require?
On the whole, charred timber cladding is more durable than non-charred cladding and will last decades, especially if properly maintained. The timber species plays a large role in the durability of the cladding as different species char more or less effectively. As mentioned above, the thicker the carbon layer that is formed, the longer the cladding will last.
Keep in mind that exposure to weather elements can also affect the aging process. Cladding used indoors away from direct sunlight will generally require less maintenance than exterior cladding which receives direct sunlight, wind and rain throughout the day.
Maintaining Shou Sugi Ban cladding requires little more than re-coating in oil every 2-4 years, depending on the timber species, the location and the level of exposure to weather elements. Enquire with your timber supplier for recommendations on how often to coat your cladding with oil.
How Often Should Shou Sugi Ban be Oiled?
Shou Sugi Ban cladding should be supplied with a coat of oil before it is delivered to the project site. Once it has been installed, a second coat should be applied.
A third coat should be applied 4-6 weeks later. Spacing the second and third coats out is important so that the oil can soak into the timber.
Further coats should be applied periodically, according to the supplier’s recommendations.
- For Burnt Ash Shou Sugi Ban, recoating every 3 years is a good practice, but it can be left up to 5 years depending on the level of exposure to the elements.
- Jarrah Shou Sugi Ban should be re-coated every 2-4 years depending on where it is installed and the level of sun exposure.
- Spotted Gum Shou Sugi Ban should be re-coated every 18 months-2 years.
How to Clean Shou Sugi Ban Timber?
Shou Sugi Ban cladding does not require much upkeep and cleaning is not usually necessary. However, if the cladding has visible signs of dirt or stains it can be cleaned via a fairly simple process.
Use a soft bristled broom and sweep in the direction of the timber. Use warm soapy water or special timber cleaning products for any stained areas. Make sure any products you use are compatible with the oil coating used on the timber cladding. For interior Shou Sugi Ban timber, simply wipe down the timber with a damp cloth. If you use a cleaning product test a small area to make sure it doesn’t cause damage to the timber.
So many Reasons to fall in Love with Shou Sugi Ban
As with any investment, it is important to know what the long term requirements are before choosing to go with Shou Sugi Ban cladding. The good news is Shou Sugi Ban lives up to its reputation.
It’s highly durable, doesn’t require much maintenance over time and offers the beautiful textures of real timber. Plus, the handmade process of Shou Sugi Ban stands in stark contrast to all the mass produced, synthetic building materials out there. There are so many reasons to fall in love with charred timber cladding.