10 March 2025

Protecting the fabric of the building with reliable waterproofing has always been vital, and now NHBC’s Technical Guidance 9.2/06 ‘Substrates for tiling bath and shower enclosures, wet rooms and bathroom pods’ reinforces this. In essence, any new home whose foundations begin on or after 1st January 2025 in the UK must comply with this guidance if an NHBC warranty is to be provided.

Understanding NHBC’s latest requirements

Projects must not include magnesium oxide boards, and only tile backerboards with NHBC-approved technical certifications are permitted in wet rooms or bathrooms with power showers. All tanking solutions require third-party certification, such as a European Technical Assessment (ETA), and tiles, adhesives, and grout must be compatible with the chosen waterproofing system.

Does your new build project have a bathroom or wet room?

New build projects with bathrooms or wet rooms can rely on wedi for compliant solutions. Its 100% waterproof, directly tileable XPS boards and shower formers meet NHBC’s latest requirements, holding certifications such as Environmental Product Declarations (EPD), A+ VOC label, European Technical Approval (ETA), and CE, UKCA, and UKNI markings along with BBA certificates.

Simplifying specification with a complete waterproofing system

Using wedi building boards to waterproof floors and walls in wet rooms and bathrooms can streamline installation, reducing steps and minimising the risk of failure. When combined with interlocking components such as floor-level shower elements, benches, niches, and ready-to-use partition walls, these systems provide a comprehensive, floor-to-ceiling waterproofing solution that industry professionals have tested for over four decades.

Since September 2021, when wedi joined the Ardex Group, a range of compatible grouts and adhesives can also be provided under one comprehensive 10-year product warranty. Choosing a single-source solution with complete manufacturer accountability allows architects to remain focused on the design.

Product characteristics, such as a 133kg/m² vertical weight-load capability, make wedi building boards suitable for various tile, natural stone, and slab coverings. When used with reinforcement plates, they can also support larger fixtures, including floating washbasins, doors, and radiators, meaning multifunctional partition walls can be created quickly and easily, ready for tiling the next day.

Additionally, with a low U-value of 0.036 W/mK, these boards contribute to indoor thermal insulation and overall energy efficiency. Suitable to use beneath under-tile heating (UTH) systems, they provide a 100% waterproof substrate for hot-water and electric under-tile heating systems.

Supporting the Future Homes Standard

With the Future Homes Standard coming into effect in 2025, all new homes must be designed with improved energy efficiency and where possible with low-carbon heating, reducing carbon emissions by 75–80%. While wedi building boards do not directly reduce carbon emissions, wedi’s solutions create the optimal conditions for integrating energy-saving technologies.

To support energy-efficient and future-proof bathroom designs, innovative building boards have been developed to accommodate modern heating systems. The increase of heat pump-operated water heating systems prompted the development of the wedi PreLine building board.

Featuring factory-cut grooves for precise pipe installation, they prevent heat loss and improve system response times by up to 70%. The grooves help prevent accidental damage during floor covering installation while ensuring pipes are laid evenly and close to the surface. Once installed, the pipes are backfilled with tile adhesive before tiling. These boards can be applied to both floors and walls.

wedi offers a variety of floor-level shower elements in multiple formats to accommodate a large number of applications. Options include linear or point drainage systems, in standard, rectangular, round, and shell-shaped designs with matching free-standing walls. The wedi Fundo range provide flexibility in design and ease of installation while maintaining full NHBC compliance.

Flexible, future-proofed design with Fundo solutions

Slim design, flexible solution - the latest addition to the Fundo range flexibly adapts to design requirements. The channel element and the narrow 35mm-wide channel profile can be cut to size and positioned close to the wall, centrally, or anywhere between to suit a wide range of project requirements.

The Fundo Flex shower solution introduces a new level of adaptability, an innovative approach to bathroom design. With stepped rebates on either side of the channel element, the complementary sloping boards allow for securely extending the installation into a fully-sealed shower floor, offering a complete, customisable linear shower system. The system can be installed in/on wood or screed, with or without complementary sloping boards to suit all requirements.

To meet NHBC’s latest technical guidance, a precise, even gradient must also be ensured. Providing a secure connection, wedi Fundo sloping boards offer enhanced reliability for the entire shower floor. These boards can also be shortened, allowing for a bespoke design tailored to project requirements.

The Fundo Flex system delivers a modern, precision-engineered shower floor without compromise, offering both design flexibility and ease of installation while maintaining high performance and reliability.

For more information on how wedi can support NHBC-compliant design, visit: www.wedi.net. For specification information, discover wedi on NBS Source.