Z275 Galvanized Spiral Duct for All-Air & Heat Recovery Systems – Complete Range of Sizes and Fittings

Ductwork carries more than air — it carries the performance of the whole system. In all-air conditioning and heat recovery installations, poorly made ducting means leakage, pressure loss and noise that no amount of unit maintenance can fix.

Our Z275 Galvanized Spiral Duct is machine-formed from galvanized steel strip with a 275 g/m² zinc coating on both surfaces — strong, smooth and airtight, available from Ø80 to Ø1500 mm with a complete matching fittings range for all-air and heat recovery systems.

Design & Construction

The duct is roll-formed from high-quality galvanized steel coil into a continuous spiral lock-seam tube. The helical seam does more than join the metal — it acts as a reinforcing rib, giving the round duct exceptional rigidity for its weight.

• Z275 galvanized protection — 275 g/m² zinc coating, corrosion-resistant inside and out;
• Spiral seam reinforcement — high strength-to-weight ratio, less material, lighter handling;
• Smooth internal bore — low airflow resistance, less dust accumulation, quieter operation;
• Airtight construction — continuous machine-formed seam minimizes leakage along the run;
• Full size range — Ø80 – 1500 mm to match any design;
• Complete fittings range — elbows, reducers, tees, branches, dampers, couplings and flanges from one supplier.

Key Features & Specifications

Where It Works — Typical Applications

Built for ducted air systems that need reliable, low-leakage performance over a long service life:

• All-air air conditioning systems — supply and return mains from the air handling unit to zones;
• Heat recovery / ventilation systems — fresh-air and exhaust duct networks with balanced airflow;
• Commercial buildings — offices, hotels, shopping malls, schools and hospitals;
• Light industrial ventilation — workshops, factories and storage areas;
• Long straight runs & concealed installation — above ceilings and in risers, where round duct saves space and cost.

Get in Touch — Service & Support

A duct system is only as good as its weakest joint. With Z275 Galvanized Spiral Duct and a complete matching fittings range from one supplier, your project stays consistent in quality from the first meter to the last fitting — no mixed sources, no mismatched parts.

We supply standard sizes from stock and support custom diameters and cut-to-length orders. Contact our sales team for datasheets, a full fittings catalog and project pricing.

Related products: Spiral duct fittings · Insulated HDPRE semi-rigid duct · Duct silencer