Spiral staircases The main characteristics of spiral staircases or a round staircase are their central columns and a compact, circular staircase design, which means relatively little surface area is required for installation. Experienced spiral staircase manufacturers, including a spiral metal staircase, provide a wide choice of materials and design options ensuring that the resulting stair suits the space it is created for. Double Staircase, Staircase Design, Wooden Staircases, Luxury Dining Room, Contemporary Home Decor, Stair Treads, White Oak, Ground Floor