Shou Sugi Ban Charred Wood Products

Kiertopuu®️ – Upcycled Residual Wood with Shou Sugi Ban Charred Surface

Kiertopuu®️ is a Finnish Circular Economy Product

Kiertopuu® products are made from residual wood or inferior quality wood generated by the sawmill, planing, and construction industries. The material is mainly Finnish spruce, originally having bruises, poor knot quality, color defects, or not suitable for structural use according to its strength classification. However, this material can be cleaned by charring its surface and repurposed for use as cladding material. If it is not used for cladding, it is often burned for energy.

In the charring process, we use Finnish biogas instead of fossil fuels.

Shou Sugi Ban / Yakisugi: Wood Surface Treatment by Burning

The idea of wood surface treatment and protection through burning originates from Japan, where the method is known as shou sugi ban (also yakisugi). In English, we talk about wood surface charring.

Burning the wood’s surface removes sugars and organic matter from the wood, and it seals the wood’s pores. This treatment:

  • Improves the wood’s weather resistance
  • Cleans the wood’s surface
  • Offers a non-toxic way to protect the wood
  • Doesn’t weaken the wood’s internal structure
  • Doesn’t smudge when the wood surface is washed, brushed, or oiled after charring

Surface Treatment Options for Kiertopuu®️ Products

Information about Charred Kiertopuu®️ Products

From the table below, you can find the main forms, dimensions, and use cases for Kiertopuu®️ products, which are available in lengths ranging from 1000 – 6000 mm depending on the available raw material.

panel22 x 50-250
28 x 50-250
interior cladding
exterior cladding
board16-28 x 64-250fences, structures, docks, terraces
plank44 x 64-244terraces, railings, docks
beam50-200 x 50-200posts, railings, docks

Ordinary Sawn Timber Charred with Biogas

Any type of wood can be surface-charred with our method. Should the need arise for a more specialized material or dimension, please contact us. We also char new wood ecologically with biogas as needed.

Wood Surface Charring as a Service

We also offer wood charring as a service to wood industry operators. This charring is also done more ecologically with biogas. For more information, please contact us.

Request a Quote

To request a quote for Kiertopuu products or other surface-charred woods, fill out the form. You can also email the requested information to

Our staff will reply with a quote, shipping costs, and possible delivery time or ask additional questions about your needs.