Spiral Duct

Galvanised lock seam spiral duct for ducted air conditioning, mechanical ventilation, and commercial HVAC trunk line applications. Manufactured using a 4-ply spiral lock seam construction, this duct offers superior rigidity compared to longitudinal seam ductwork, with a smooth interior that minimises air resistance and pressure drop — making it well suited to medium and high velocity systems. The galvanised steel construction provides lasting corrosion resistance for reliable performance in ceiling spaces, plant rooms, commercial fit-outs, and industrial ventilation applications. Compliant with AS4254 and compatible with standard spiral duct fittings including elbows, reducers, and tees. Available in 1m lengths from 100mm to 600mm diameter, with same-day dispatch from our Thomastown warehouse. Sizes available: 100mm · 125mm · 150mm · 200mm · 250mm · 300mm · 350mm · 400mm · 450mm · 500mm · 550mm · 600mm