Bamboo X-treme® cladding in Courtrai
Bamboo decorates the façade of an apartment complex in a safe and sustainable way
February 2019. MOSO, Zwaag/NL.- Commissioned by the social housing company, Cheap Dwelling, the two existing apartment blocks in the Drie Hofsteden in Kortrijk have been thoroughly renovated. At the same time, a third apartment block was built. This renovation project is partly a component of an ECO Life project with European subsidies and partly an IWT project. The ambition level for the renovation is so-called BEN; for the new construction this results in low energy consumption. In order to give the project a natural look, MOSO Bamboo X-treme® was selected for finishing the façade of the new building. The ecological advantages of the CO2 neutral cladding fit in very well with this project.
Fire safe bamboo cladding
The Drie Hofsteden complex consists of three apartment blocks. "The façades of the other two buildings are made of white crepi with panels, wooden slats and white metal. For the intermediate building, we wanted to make wood the main material of the façade," says ir. -arch. Nancy Latruwe of B2Ai. "However, according to Belgian legislation for medium and high-rise buildings, cladding must comply with class B-s3, d1 with regards to reaction to fire. Without fire retardant treatment, no wood known to us meets this class, which is slightly stricter than the class A2 from the KB fire rating system before 2012. In contrast to soft woods, such as pine, tropical hardwood is difficult or impossible to impregnate in the autoclave. Such treatment with a fire retardant is, in any case, environmentally harmful and requires maintenance. We were pleasantly surprised when a colleague discovered that Bamboo X-treme® does not need to be treated with flame retardant to comply with class B-s3, d1. The choice of wood species for this project was, therefore, quickly made.
The apartments were completed in July 2018 and have all been inhabited since then. "The result is aesthetically pleasing. Given that the reaction of the insulation behind a façade with open joints also had to be taken into account in the event of fire, a closed façade was chosen. This was necessarily the oiled version because it is the only version with tongue and groove available. We thought that this would cause the façade to discolour very slowly, but that's fine. Also the weather conditions, with the very warm summer and wet autumn, have hardly had any additional effect on the façade. The discolouration remains in different shades of brown, but the result shows out very well. You also keep seeing that it is wood," says an enthusiastic architect.
"A fire-resistant treatment costs about 17 euros per square metre. You get a 10 year warranty on it, but if you read the warranty conditions carefully, you have to carry out local repairs about every two years and that involves an aerial work platform. We actually wanted to get rid of this environmentally unfriendly system of treatment. Bamboo proved to be the perfect alternative. After installation, façades with Bamboo X-treme® cladding do not require periodic maintenance. Due to the high stability, the planks remain flat in place in contrast to other natural materials. The savings are, therefore, not only in the treatment, but also in the maintenance of the façade. The total cost over the lifetime of the façade are thus lower," concludes the architect. Due to the great satisfaction with the use of bamboo in this project, B2Ai has now also used bamboo as cladding in other projects.
MOSO Bamboo X-treme® cladding consists of solid bamboo planks made of thermally modified and compressed bamboo strips. Thanks to the unique Thermo-Density® production process, Bamboo X-treme® achieves the highest durability class, according to relevant EU standards, and greatly increases stability and hardness. The use of tropical hardwood is linked to deforestation. While it can take up to 80 years before the tropical hardwood can be cut down, MOSO bamboo stems grow into a mature plant after only 4-5 years. After harvesting, the bamboo plant does not die off and there is no deforestation. On the contrary, new stems will grow from the mother plant even more and at an increased rate. In this way, bamboo can be harvested annually and a bamboo plantation is sustainable and fair trade for the farmers. Bamboo products are the sustainable alternative to tropical hardwood and other less environmentally friendly materials.