Fundo Solido

Standard XPS cores are optimised for typical bathroom applications. However, under soft surface coverings such as PVC flooring, very high point loads can occur, for example from wheelchairs or medical equipment. 

To reliably withstand these loads, Fundo Solido features a 100% recycled PET core with an exceptional compressive strength of 4 N/mm². This ensures long-term dimensional stability and resistance to indentation under concentrated loads. 

Fundo Solido is directly bonded to the prepared subfloor using flexible, cement-based tile adhesive — installed in the same way as other wedi Fundo shower elements. 

Depending on the condition of the PVC, a levelling layer may be required. If a sealed substrate is desired, the perimeter areas must be sealed with sealing tape, and the joints must be bonded with wedi 610. After the levelling compound fully cures, flexible PVC flooring can be directly bonded to the surface. 

Sealing tape ensures waterproof joints at transitions between Fundo Solido and adjacent building elements. 

Levelling serves a different function: it creates a smooth and even substrate required for bonding flexible PVC flooring and ensures uniform load distribution. It is a necessary preparation step for the floor finish. 

Yes. Fundo Solido and the extension boards are inherently waterproof. When connecting wedi elements, joints are bonded and sealed using wedi 610, which provides both adhesion and waterproofing in one step. Additional surface waterproofing is not required between wedi components. Sealing tape is only necessary at transitions to adjacent building elements. 

Yes, cutting is possible within defined limits. Due to the four-sided slope design, trimming must be carried out symmetrically — any reduction on one side must be mirrored on the opposing side to preserve the slope and ensure proper drainage. 

Fundo Solido can be customised using common hand or electric saws. Cutting produces low dust levels; however, standard jobsite safety measures and local health regulations must always be followed. 

Yes. As the extension boards do not incorporate a predefined slope, they can be cut to suit the required layout. 

This provides flexibility during installation, for example when adjusting the position of the shower element to avoid structural elements such as joists or when creating precise transitions to surrounding floor areas. 

Since the extension boards do not provide drainage, their placement must ensure that water flow towards the shower area is maintained and standing water is avoided. 

The slope can be created in the subfloor and then covered with the extension boards. Alternatively, the subfloor can be prefabricated with the required slope - for this option, please contact our project department for further details. 

PVC flooring with a typical thickness of 2–4 mm can be installed on the Fundo Solido without any issues. 

For wet areas, the PVC flooring must be installed as one continuous sheet over the entire Fundo Solido surface. Installations using separate strips are not supported and are not covered under the wedi warranty, as a continuous surface is required to ensure watertightness. 

The slope of a Fundo Solido depends on the selected format. The exact slope for each format is specified in the corresponding technical drawing available in the download section of the product page. 

In principle, special size elements are possible. The maximum size depends on the specific design and the overall scope of the project. 

A screw on drain cover is used for safety reasons. It prevents unauthorized removal of the cover, which is important in high security environments such as correctional facilities or other supervised institutions. 

Although the clamping ring provides mechanical fixing, bonding the flooring into the drain ensures a secure and watertight connection. The adhesive prevents movement and supports long-term sealing performance. Installation must follow the current wedi installation instructions. 

Yes. As the core consists of 100% recycled PET, colour variations from green to grey are normal. These variations do not affect product performance or quality.