Yoroi | Fire-safe charred bamboo for uncompromising façade architecture
B-s1,d0 fire performance. No chemical fire retardants. A bio-based material with a powerful architectural identity.
As architecture moves towards a lower-carbon future, façade materials are expected to do more. They must meet demanding fire-safety requirements, reduce embodied carbon, perform reliably for decades and contribute to the architectural identity of a building.
Yoroi brings these demands together in one distinctive façade material.
Developed by Zwarthout | Shou Sugi Ban, Yoroi is a deeply charred façade cladding made from FSC®-certified MOSO® Bamboo X-treme®. Its intense black, tactile surface gives buildings a powerful architectural presence, while the material behind it offers the technical performance required for demanding contemporary architecture.
Fire safety without chemical fire retardants
Fire safety increasingly influences material selection and façade design, particularly in public and commercial buildings.
Yoroi achieves B-s1,d0 fire classification according to EN 13501-1, without chemical fire retardants, fire-retardant impregnation or additional surface coatings.
This gives architects the opportunity to specify an expressive, natural façade material while meeting demanding fire-performance requirements.
The combination of high-density, thermally modified bamboo and a controlled charring process creates a dense carbon surface with a distinctive architectural character.
The result is a rare combination: certified fire performance and natural materiality within one façade solution.
A bio-based material for lower-carbon architecture
As operational energy use decreases, the embodied carbon of building materials becomes increasingly important.
Bio-based materials offer architects the opportunity to reduce reliance on more carbon-intensive façade systems. Bamboo is a rapidly renewable resource that absorbs CO₂ during growth and stores biogenic carbon throughout its service life.
MOSO® Bamboo X-treme® offers documented environmental performance through LCA and EPD data, helping architects assess material choices within broader sustainability strategies.
Combined with a long service life and low maintenance requirements, Yoroi supports a more resource-conscious approach to façade design and can contribute to certification pathways such as BREEAM and LEED.
Designed to remain
A façade is exposed to rain, wind, sunlight and temperature changes for decades. Material stability therefore has a direct impact on the long-term quality of the architecture.
Yoroi is based on high-density, thermally modified bamboo with durability class 1 according to EN 350, the highest European durability classification.
Its high dimensional stability limits swelling, shrinkage and deformation. The material is highly resistant to biological degradation and requires little maintenance.
For architects, this means more than durability.
It means greater predictability between the façade that is designed and the façade that remains.
A surface shaped by fire
Technical performance alone does not create architecture.
Yoroi’s identity comes from its deeply charred surface. Up close, the carbon layer reveals texture, depth and irregularity. From a distance, the material can unify a building into a strong, almost monolithic volume.
Light continuously changes the façade. In direct sunlight, the surface reveals subtle reflections and tonal variation. In shadow, it becomes deeper and more abstract.
Yoroi can strengthen a building’s geometry, anchor it in the landscape or create a powerful contrast with concrete, glass, metal and other natural materials.
Fire-safe. Bio-based. Built to last.
Yoroi — for architecture without compromise.
