Classic Travertine Split Face Ledger Panel

Its practical questions deserve more attention than its colour. A split face panel is thick and irregular, so it weighs considerably more per square metre than a sawn tile. The substrate has to be sound, and a plasterboard wall generally needs additional support or a cement board overlay before anything is fixed to it. Adhesive coverage matters as well: an uneven back face means a notched bed alone can leave voids, so panels are usually buttered as well as combed.

The format is also one of the few here that works outdoors. Travertine is porous and will take up water, so an external installation needs a sealer intended for exterior use and a detail that keeps the bottom edge of the panel clear of standing water and splash-back.

Indoors it belongs on chimney breasts, feature walls, bar fronts and alcoves. Its crevices make it a poor surface anywhere that needs regular wiping, and a broken face cannot be refinished afterwards.