On request, we can apply a fire-retardant treatment to our wood for façade, ceiling and wall cladding. This 100% biodegradable treatment guarantees that our timber profiles meet the required reaction-to-fire class without altering their colour or structure. What's more, Carpentier can provide the necessary certificates for closed and open-joint cladding.
Despite the natural resistance wood offers against fire, untreated timber cladding, wood ceilings and wood walls will never be able to meet the reaction-to-fire class required for project construction and private housing. If that is the challenge you face, a fire-retardant treatment is the ideal solution.
At Carpentier, all sustainable wood varieties can be given a fire-retardant treatment. This is done under vacuum pressure in an autoclave — a 100% natural, biodegradable, energy-efficient and pH-neutral process. There is no change in colour or structure. A temporary white film may form on the surface, as a natural result of the drying process. This is easily removed with a brush, cloth or water.
Thanks to the fire-retardant treatment in the autoclave, our closed cladding profiles in HOTwood ash achieve reaction-to-fire class B-s1,d0 and those in HOTwood Pine and Clear Pine achieve reaction-to-fire class B-s2,d0, provided the profiles are fixed traditionally. Our half-lap shiplap profile with clip system also meets this classification.
Recently we have also been offering open-joint cladding that meets fire class B. Carpentier is working with Grad on a patented installation system with a fire-resistant clip, allowing open-joint cladding with joints of up to 30-35 mm to meet fire class B as well. This innovation is scheduled for launch in the second half of 2026.
After the treatment, we can provide a certificate. This opens up more possibilities for architects to use wood as a building material in their designs.
Carpentier offers fire-retardant timber cladding that meets fire class D or fire class B without any fire-retardant treatment.
Thermo bamboo achieves fire class B-s1,d0 naturally, without any additional treatment.
A fire-safe timber construction consists of more than just the cladding. For the complete build-up, we also offer additional fire-retardant products:
Fire-retardant treated softwood battens, painted black (B-s2,d0) — ideal as a substructure. Durable cement-bonded fibre board Flame Delay® WP-A2 for an extra fire-safe build-up. Fassawall FireStop A2 façade membrane: non-combustible, UV-resistant, water-repellent and temperature-resistant.
This way, as an architect or contractor, you can deliver a complete, fire-safe solution — from substructure to finish.
A fire-retardant treatment need not mean any compromise on appearance. The wood retains its colour, structure and character — with the assurance of a fire class B certificate.
Whether you need to apply cladding with a D or B classification largely depends on the height of the building. A fire-retardant treatment is in principle only required for high-rise buildings (from 10 metres) and applies mainly to industrial buildings, hotels and hospitals.
For more information on the Belgian fire safety requirements and the required reaction-to-fire performance, we have prepared a clear whitepaper.
After treatment you receive a certificate proving that the timber has passed a fire test in accordance with the applicable European standards. As an architect, contractor or timber merchant, you can easily download the certificates via our customer zone.
Not sure whether a fire-retardant treatment is required for your project, or which solution suits best? We are happy to think along with you and advise you on the right approach. Get in touch and we'll discuss the options together.
