I’m planning a full-steel spiral staircase built from structural pipes, sized to fit a 1.8 × 18 m floor footprint and rising 3.5 m from finished floor to the upper slab. The steelwork has to arrive powder-coated straight from your shop so it’s ready for final installation on site. The idea is to bolt or weld the pipe stringer and riser framework together, leaving each tread with a clean, flat plate where we can later secure hardwood overlays. I haven’t locked in the timber species yet, so please allow fixing points that will accept anything from oak to walnut once I make that call. I need a continuous handrail on the outer curve only, fabricated from the same pipe stock or a complementary section so the overall look is seamless. Deliverables • Detailed fabrication drawings showing pipe diameters, tread plates, central column, and handrail geometry • A step-by-step erection plan with anchor locations for both slab levels • The finished, powder-coated steel kit, ready for transport and on-site assembly • A brief maintenance guide outlining paint touch-up procedures and recommended load limits If you’re confident with spiral stair calculations, pipe work, and shop-applied powder coating, let’s discuss lead time and any questions you have about clearance, baluster spacing, or code compliance.