Marble staircase restoration in Milan

Milan’s buildings mainly have three kinds of staircase. Solid steps, each cut from a single block, are found on older and grander stairs; they are thick and can take deep grinding. Clad steps are marble slabs a few centimetres thick bonded onto a concrete or brick structure, so the available thickness is limited and every millimetre removed has to be judged carefully.

Cantilevered stairs, with each step built into the stairwell wall on one side only, feature in some nineteenth and early twentieth-century buildings. They look light and elegant, and they call for a gentle approach: no heavy machines, no knocks, and carefully controlled wet work so water does not run into the wall joints. Before starting we always check the stone and look for structural cracks; anything beyond the marble itself is flagged before work begins.

The stone changes with the period too: Carrara and bardiglio on nineteenth-century stairs, Botticino and Ceppo di Gré in many twentieth-century blocks, coloured marbles and granites after the war. Each has its own hardness and needs its own sequence of abrasives.

A mirror-polished staircase looks superb, but a sloping route that people often take in a hurry needs grip. On treads we therefore often suggest a honed or satin finish: smooth to the touch, yet the micro-texture left by a medium grit helps soles hold, especially when the stone is damp. Risers, skirting and balustrade bases can still be taken to a full polish, giving a pleasing contrast between the walking surfaces and the decorative ones.

This avoids film-forming anti-slip products, which wear unevenly and yellow over time. The grip comes from the stone itself rather than an added layer.