Galvanised vs Stainless Steel Ductwork: Which Do You Need?

Most commercial ductwork in the UK is galvanised steel — and for good reason. But there are environments where stainless steel earns its premium.

Galvanised steel: the default for good reason

Hot-dip zinc-coated mild steel protects against corrosion in normal indoor conditions, folds and seals beautifully, and is what DW144 is written around. Right for offices, schools, retail, warehouses and almost every general supply and extract application.

Where stainless steel earns its place

Stainless resists corrosion through its chromium content, so it keeps protecting when cut or scratched. Choose it for commercial kitchen extract with aggressive cleaning regimes, swimming pools where chloramines attack zinc, coastal or polluted external runs, food and pharmaceutical hygiene areas, and corrosive process extract.

Cost, grades and practical compromises

Stainless costs several times the galvanised equivalent. Grade 304 covers most internal hygiene applications; grade 316 adds chloride resistance for pool halls and coastal exposure. A common-sense compromise is stainless only in the wet or corrosive zone, transitioning to galvanised beyond it.

What about DW144?

DW144's gauges, stiffening and sealing principles carry across to stainless fabrication — the same folded, seamed and sealed construction in the corrosion-resistant material.

Talk to us about your project or price galvanised ductwork online.