Steel sheet for HVAC ducts
Duct shops and air-conditioning contractors buy galvanized (GI) sheet from us as full sheets, or cut and bent into panels, flanges and fittings ready to assemble.
Typical GI thickness by duct size
| Largest side of the duct | Typical GI thickness |
|---|---|
| Up to 300 mm (12 in) | 0.5 – 0.6 mm |
| 300 – 750 mm (12 – 30 in) | 0.6 – 0.8 mm |
| 750 – 1350 mm (30 – 54 in) | 0.8 – 1.0 mm |
| 1350 – 2100 mm (54 – 84 in) | 1.0 – 1.3 mm |
| Over 2100 mm (84 in) | 1.3 mm and up |
Typical values for low-pressure rectangular ducts. Your consultant's specification always comes first. Gauge numbers differ between standards, so we quote thickness in mm.
Galvanized for damp air
GI sheet resists the condensation that rusts plain steel inside ducts and plenums.
Cut and bent to your drawing
We CNC cut and press-brake bend parts in Okara, so you get finished pieces instead of full sheets to cut yourself.
Mill-certified sheet
HR, CR and GI sheet and MS plate from 0.5 to 25 mm, with mill certificates for every bundle.
Duct parts we cut and bend
- Straight duct panels and wraps
- Elbows, reducers and transitions
- Duct flanges and corner pieces
- Plenums and boxes
- Damper blades and frames
- Kitchen hood panels
- Support brackets and hangers (MS angle and strip)
- Access door panels
Common questions
What thickness of GI sheet is used for ducts?
For low-pressure rectangular ducts, a common guide is about 0.5 to 0.6 mm for ducts up to 300 mm on the largest side, rising to around 1.0 to 1.3 mm for ducts over 1350 mm. Always follow your consultant's specification.
Can you cut and bend duct panels to size?
Yes. Send us the duct schedule or drawings and we can CNC cut and press-brake bend panels, flanges and fittings so your team only has to assemble them.
Do you sell full GI sheets to duct shops?
Yes. We supply galvanized sheet as full sheets in common sizes such as 4 × 8 ft, for shops that cut and fold in-house.
Can you make duct supports and brackets?
Yes. We cut and bend support brackets, hangers and frames from mild steel angle, strip and plate.
Send us your sizes or drawings
Tell us the grade, thickness and quantities, or send a DXF. We'll reply with a price and a ready date.