Suitable Substrates

The perfect finish requires perfect preparation

By Carl Stokes, Head of Marketing, Schlüter-Systems Ltd.

With installations becoming ever more demanding, and large-format tile and stone the standard, a waterproof backerboard that has been designed with these materials at heart is the reassurance that every specifier needs.

The desire for the perfect finish is universal, but this can only be achieved by using an absolutely level substrate that is ready to tile. In this respect, Schlüter®-KERDI-BOARD fits the bill perfectly, and offers many other useful features besides.

A flexible and multi-functional solution
Schlüter®-KERDI-BOARD is the cement- and fibreglass-free, multi-functional installation board, suitable for use in both renovation and new-build projects. Providing a flat and even substrate and enabling precise angling of corners, seven thickness options are available, ranging from 5 to 50mm. While the boards at the thinner end of the spectrum are designed for use over existing substrates, latter thicknesses can be used as construction panels to create features such as shelves, partition walls and seats, allowing for unbridled freedom of design.

CE Marked waterproofing
Proper moisture management is essential to guaranteeing successful long-term performance. In no area does this ring truer than a wetroom or bathroom. When specifying for these areas, a key point to grasp in order to ensure a finish that is fit for purpose is the difference between waterproof and water-resistant backerboards. Whereas waterproof boards do not allow water to penetrate their surface, water-resistant boards allow water to pass through. This means that water-resistant boards alone cannot provide adequate protection for a tile or stone installation; they will always require an overlay with a liquid applied or sheet based waterproofing membrane. With a waterproof backerboard, this additional process is not necessary, saving significant time on-site.

Schlüter®-KERDI-BOARD provides CE Marked bonded waterproofing, with no need for additional finishing processes. Using the various accessories available from the Schlüter®-KERDI range, the seams between individual boards are quickly and robustly sealed, creating a complete CE Marked bonded waterproofing assembly upon which tiling can commence without delay.

Preformed pieces for easy designer features
As well as the standard boards, a number of other products are available as part of the Schlüter®-KERDI-BOARD family, including Schluter®-KERDI-BOARD-N, a collection of fully sealed, prefabricated niches for the quick creation of stylish recessed shelves. Design possibilities extend beyond flat planes of construction courtesy of Schlüter®-KERDI-BOARD-V, a grooved version of the board, specifically designed for the purpose of creating curved and rounded features.

For contractors, a move to Schlüter®-KERDI-BOARD represents a quicker and easier installation process, with time savings being made due to its light weight and ease of cutting.

Environmentally-friendly composition
Schlüter®-KERDI-BOARD makes for a considerably greener alternative to other options, such as plasterboard and cement-faced products. Its construction consists of an extruded hard foam core panel, with a special reinforcement material on both sides and waterproof fleece faces to finish, providing effective anchoring in the tile adhesive. The foam core of Schlüter®-KERDI-BOARD is thermally insulating, helping to conserve energy use and improve comfort. The absence of a cementitious layer means that it costs less to transport and produces no dust when cut, making for healthier working conditions and avoiding release of toxins into the wider environment.

Installation processes and finishing touches
Dependent on the background that it is being installed onto, Schlüter®-KERDI-BOARD is either fully embedded into tile adhesive or screw-mounted. The latter method is used for installation upon professionally constructed stud frames and the areas where the screws attach are easily waterproofed using Schlüter®-KERDI-KEBA sealing bands and Schlüter®-KERDI-COLL adhesive.

A great finish is achieved through attention to every aspect of an installation. To protect the edges of tile and stone once they are installed, various Schlüter®-PROFILES are readily available, in a wide range of colours, materials and finishes.

The Application Gallery
Schlüter®-KERDI-BOARD can be viewed in action alongside other products from Schlüter’s comprehensive portfolio of practical solutions for tile and stone at The Application Gallery. This purpose-built space at Schlüter’s UK offices in Leicestershire presents Schlüter products in situ across seven different ‘pods’, offering an excellent source of design inspiration and product insight. They include a walk-in wetroom, barrier-free bathroom, wellness space, lifetime home, luxury wetroom and kitchen diner, along with a preparation pod which fully exposes the underlay of a Schlüter bathroom. This final pod showcases the various products of the Schlüter®-KERDI-BOARD range, plus waterproofing membrane Schlüter®-KERDI-200, all sealed with Schlüter®-KERDI-KEBA sealing bands and Schlüter®-KERDI-COLL adhesive.

As an integral part of the Schlüter-Systems Education Centre (SSEC), The Application Gallery sees extensive use during training sessions, adding a new layer of understanding to the learning experience, and also provides a unique setting for events. The facility has been produced in collaboration with leading bathroom specialists, Roca, who also have offices in the same county.

London showroom at 49
Leather Lane
Schlüter-Systems now has a permanent London home, in the architectural heartland of Clerkenwell. 49 Leather Lane is a showroom produced in collaboration with Pentagon Tiles and Ardex, and features numerous of Schlüter’s innovative tile and stone solutions – from waterproofing systems through to underfloor heating and profiles – both installed and in sample form.

Award-winning practice, Simon Astridge Architecture Workshop, was engaged for the project, which utilises recycled shipping containers and fired clay detailing to redefine the commercial showroom and perfectly chime with the area’s industrial heritage. Architects and specifiers are invited to hold meetings at 49 Leather Lane, where they can observe the details incorporated into the renovation, experience products in situ and gain inspiration; a meeting room and hot desking office are available for booking.

Schlüter Approved Installer Network
The Schlüter Approved Installer Network (SAIN) allows approved installers who have completed full training with Schlüter-Systems Ltd to install Schlüter®-KERDI-BOARD, enabling them to prepare the necessary areas as part of the dry-lining package of works ready for the tile or stone contractors. This prevents delays associated with unsuitable substrates for tile and stone that require additional preparation and remedial actions.
The network not only gives accreditation to the individual but also to the company as a certified organisation. This provides reassurance to you as the specifier or architect that the system will be installed to the manufacturer’s standards and best practice, and minimises installation risks, ensuring a robust, reliable installation.

Learn more about specifying substrates
The importance of specifying waterproof rather than water-resistant backerboards for tile and stone is a key topic covered in our CPD seminar ‘Specifying Integrated Solutions for Waterproofing and Wetroom Systems’. Enhance and reaffirm your knowledge with this 45 to 60 minute presentation, held at your offices.

This CPD also covers other key considerations for the construction of a wetroom that is fully fit for purpose, including: the benefits of integrated systems for wetrooms versus multi-manufacturer combined offerings, how point and linear drains can be hidden or accent the design, the requirements of waterproofing and how an integrated system offers peace of mind for a complete solution.

To book a CPD Seminar, call 01530 813396, email, or visit

Schlüter-Systems have dedicated consultants on hand to help with any stage of your specification project. For more information, call 01530 813396, email, or visit

NBS Clauses and BIM Objects for Schlüter-Systems Ltd are available on NBS Plus, National BIM Library and at