Don & Low, the UK’s renowned vertically integrated manufacturer, is proud to announce that MultiTX® Maxi, the new, heavy-duty barrier roof underlay, has been successfully assessed by the BBA. MultiTX® Maxi is now the only heavy-duty barrier roof underlay on the market holding a BBA Agrément Certificate.

Part of the extended MultiΤΧ® range, MultiTX® Maxi is a high vapour resistance, air and liquid barrier underlay for use in pitched roofs. Weighing 190gsm, MultiTX® Maxi provides enhanced durability and superior protection against the elements, helping to prolong the longevity of the roof. MultiTX® Maxi serves as a modern alternative to traditional bituminousbased (type 1F) roofing felts with excellent low temperature flexibility, while also being resistant to water penetration and stabilised against UV degradation.

The BBA Agrément Certificate is a mark of excellence based on rigorous national and European standards that validate a construction product’s specialist formulation, capability and uniqueness.MultiTX® Maxi has undergone a thorough evaluation that has quantified its performance. The BBA has determined that the new MultiTX® Maxi is well suited to its intended use and can satisfy all relevant requirements of the essential building regulations.

Will Campbell, Head of Sales at Don & Low, commented: “The BBA Certificate of MultiTX® Maxi represents a long history of technical competence and countless successes in our Research and Development and testing departments. As a vertically integrated manufacturer, Don & Low maintains total control over every step of the in-house production process. This allows us to maintain the highest quality standards and consistent product performance, resulting in innovative and cost-effective solutions tailored to the needs of the construction industry.

The extended MultiTX range of barrier roof underlays now consists of four products: MultiTX® Plus(116gsm), MultiTX® Pro (145gsm), MultiTX® Maxi (190gsm) and the specifically engineered for integrated solar roofs MultiTX® Solar.

The BBA Agrément Certificate for MultiTX® Plus, MultiTX® Pro and MultiTX® Maxi can be found here.

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