Clay panel walls Clay panels differ from earth blocks in size and thickness as well as method of manufacture. Thick panels are available as large-format blocks with or without tongue and groove joints and are laid with mortar or glued. They can be used as self-supporting blocks for interior walls without the need for a supporting construction. Important: Due to their precise dimensions and minimal joint gap, a thin layer of fine clay render is in many cases sufficient for the surface treatment of clay panel walls.     Lightweight clay building board Thin clay panels are normally 2 to 3 cm thick and of a similar size to conventional plasterboard panels. They are used primarily for non-loadbearing partitioning walls and are mounted on a supporting construction of wood or metal studs. Thin lightweight clay building boards are reinforced using organic fibres (for instance reed matting) so that they are stable, transportable and can be cut to size.