Stairs
trim: Trim (e.g. quarter-round or baseboard trim) is normally applied where walls meet floors. Within a flight of stairs there is no trim as the trim thickness will significantly eat into the tread width. Shoe moulding may be used between the lower floor and the first riser. Trimming a bullnose is a special challenge as the last riser above the lower floor is rounded. Today, special flexible, plastic trim is available for this purpose. Scotia is concave moulding that is underneath the nosing between the riser and the tread above it.