For most coated building coil and ACP skins, use 3003 alloy — it forms well and is corrosion-resistant. Use 1050/1100 for the cheapest, most formable decorative sheet, and 5052 where you need higher strength or marine-grade corrosion resistance, such as deep-formed panels or very exposed coastal work. The alloy sets strength, formability and corrosion resistance, so it should match how the metal is shaped and where it lives.
3003 — the building workhorse
3003 is aluminium with a little manganese: good strength, excellent formability and corrosion resistance, and it takes coating well. It is the default for PVDF coil, ACP skins, roofing and general cladding. In H24/H26 temper it is stiff enough to hold shape yet formable enough to roll and fold, which is why most building coil is 3003.
1050 / 1100 — soft, cheap, decorative
1050 and 1100 are near-pure aluminium: very formable and the cheapest, but softer and lower strength. They suit deep-drawn or highly formed decorative parts, interior trims and signage where load is low. For a structural facade skin they are usually too soft — 3003 or 5052 holds flatter.
5052 — strength and marine grade
5052 adds magnesium for higher strength and superior corrosion resistance, including salt water. Use it for deep-formed panels, structural trays, marine and very exposed coastal work, and anywhere a thinner gauge must carry more load. It costs more and is a little harder to form, so specify it only where you need the strength or the marine resistance.
What to put on the spec
Tell the mill the alloy, temper (e.g. 3003-H24), gauge, coating and use. If unsure, describe the forming (flat cladding, deep folds, marine exposure) and let them recommend — a real supplier suggests 3003 for standard cladding, 5052 for structural or marine, 1050 for soft decorative. The alloy on the mill certificate should match what you ordered.
Frequently asked questions
What alloy is used for ACP skins and coil? Mostly 3003 — good strength, formability and corrosion resistance, and it coats well.
When should I use 5052? For higher strength, deep-formed panels, structural trays or marine and very exposed coastal work.
What is 1050/1100 used for? Soft, highly formable, low-cost decorative sheet, trims and signage — usually too soft for a structural facade skin.
How do I specify the alloy? State alloy and temper (e.g. 3003-H24), gauge, coating and use; the mill certificate should match the order.
Related: PVDF aluminium coil sourcing · ACP facade panel thickness · aluminium coil MOQ & container quantity.
Talk to the factory: GSM BuildTech (Beijing Guanshimao Technology Co., Ltd.) makes insulated aluminium panels, FR aluminium composite panels, aluminium honeycomb panels, sun louvers and PVDF aluminium coil in Tianjin, China. Email sales@insulatedaluminumroof.com or WhatsApp +86 155 2274 6824 for factory-direct pricing. See the technical reference & FAQ.