However, they’re quite plain and don’t offer a grand structure like a winding or bifurcated staircase. With two clamps, the Wooden lining is mounted on a metal tread and mounted with self-tapping screws by drilled holes from underneath to the underfloor or open with bolts and screws. Missing your password? https://stairfactory.co.uk/Products/staircase-with-a-metal-stringer/