Mulderblauw architecten’s design brings together nature-inclusive construction and considered material choices. Zwarthout | Shou Sugi Ban supplied the Yoroi façade cladding: deeply charred, FSC®-certified bamboo with fire classification B-s1,d0. A biobased material that gives the hotel’s sustainability ambitions a visible, tangible expression.

Sustainable design, from landscape to material
For architects, sustainable construction calls for choices that work at every scale. At Spaarnwoude Park Hotel, this starts with its integration into the green recreational landscape and extends to the building envelope. The hotel was designed according to circular, passive and nature-inclusive principles. Green roofs and planting along the façades help capture rainwater. Nesting features provide shelter for birds and bats.

The façade cladding follows this approach. Yoroi is made from thermally modified, compressed MOSO® Bamboo X-treme®. Bamboo is a rapidly renewable resource. Life cycle assessments are available to evaluate its environmental performance, helping architects make informed material choices alongside considerations of appearance and technical performance.

Black façades as a backdrop for greenery
Long horizontal façade bands follow the contours of the hotel, continuing around its rounded corners. The vertically installed cladding boards introduce a fine rhythm to this composition. Recessed windows and overhangs add depth to the façade, while large glazed areas open the building towards the landscape.

The dark cladding provides a calm backdrop for the planting along each floor. From a distance, the façade reads as a continuous black surface. Up close, the grain and relief of the charred bamboo become visible. In sunlight, the hard carbon layer takes on a silvery glow.

Biobased façade cladding with fire classification B-s1,d0
Our charring masters char each bamboo board individually in our own furnace in Lunteren. Inspired by the Japanese Shou Sugi Ban tradition, this technique gives Yoroi its distinctive carbon layer.

Yoroi achieves fire classification B-s1,d0 without added chemical fire retardants. This gives architects a biobased façade material for projects where reaction-to-fire requirements help determine material selection. The classification reports specify the conditions for use and façade construction.

Material choices also have consequences throughout the building’s operational life. No periodic painting or staining is required to maintain the black colour. This reduces recurring maintenance work and the use of paint or stain on the façade.