Case Study

Cembrit Limited

Product: Patina Cladding Boards

Cembrit are manufacturers and suppliers of pitched roofing, rainscreen cladding and building boards to the UK market. As one of the leading European manufacturers of multi-capability, fibre-cement building products, the company develops products and solutions that offer new design opportunities with a durable yet attractive finish. However, there is no current British Standard for fibre cement rainscreen cladding, in particular their Patina range of fibre cement rainscreen cladding boards; ‘A’ fire-rated and available as coloured or natural fibre cement flat sheets.

The challenge

The lack of a British Standard meant that Cembrit were unable to provide a satisfactory certificate that signified an acceptable level of product quality and safety to potential specifiers; it is always difficult to win specifications in the UK without adequate third-party accreditation.

As the BBA can help create standards for products for which there is no existing British Standard, Cembrit decided to contact the BBA to arrange independent testing and assessment of the Patina product.

The problem was further compounded by the fact that Cembrit’s production facility was brand new when they applied to the BBA for product assessment. They had just begun the process of commissioning the production line and consequently had no production data for the BBA to audit, so full testing and Agrément Certification was needed for the company to be able to proclaim the product’s safety and fitness for purpose.

Cembrit Marketing Manager Ged Ferris said: “BBA testing holds a high-quality seal of approval. It provides peace of mind to specifiers who choose to use our non-combustible fibre cement cladding boards on their projects. BBA Certification is an endorsement of your product.”

The tests

Cladding and all forms of external wall interventions are classically subject to the effects of severe weather conditions over time. As there is no current British Standard for fibre cement rainsreen, the cladding panels needed to be tested in accordance with a number of existing British Standards.

These included water impermeability (BS EN 12467:2012), water absorption, dimensions, straightness of edge (BS EN 12467: 2012), resistance to soft and hard body impact, accelerated weathering and colour stability and resistance to algal growth.

The pull-through resistance of fixings was also tested and data assessed to evaluate wind load resistance.

Finally, BBA technical experts spent half a day witnessing the client’s installation of the wall cladding in accordance with BBA Impact Testing at the BBA premises.

Although Cembrit production facilities for the Patina product had only recently been set up, the BBA was also able to undertake an assessment of production, including an on-site audit.

The result

The assessment procedure demonstrated improvements to Cembrit’s processes which were then incorporated in the finished product. The company were happy that such a rigorous assessment process had resulted in certification that has real value to specifiers. The testing and subsequent BBA Agrément Certificate also enabled Cembrit to enhance the marketing of the Patina product, appealing not only to industrial and commercial clients but also to the private and residential sector.

A particularly successful case was when the residents of a rural Farmer’s House set in the South Downs National Park were looking to achieve an elegant extension to provide further space for their growing family. They opted for Cembrit Patina BBA Certified cladding to complement the building’s existing heritage.

The proposal consisted of a modern annexe to ensure sufficient space for their children and grandchildren and provide a link to tie the old and new structures together in an elegant form.

The architect decided to specify a wide variety of natural and man-made materials to complement the traditional geometry of the building. A Welsh slate finish to the building was desirable to both the client and architect, but a more affordable alternative was sought, and after reviewing samples, Cembrit’s BBA Certified Patina cladding provided the perfect match.

Mr Ferris added: “Our BBA Certificate demonstrates suitability for purpose which meets UK building regulations requirements which is fundamental where there is no British Standard, particularly when rainscreen claddings are under such public and official scrutiny. Possessing a BBA Certificate gives specifiers peace of mind that they are deciding on a product that will help them meet their responsibilities.”

The Farmer’s House project was a finalist for the George Clarke Medal and was also shortlisted for the British Home Awards, the AJ Retrofit Awards and the London Construction Awards, as well as being a factor in AR Design Studio being a finalist in the Architect of the Year Awards.

For more information


Tel: 0203 372 2300