What is galvanized trapezoidal sheet?
Galvanized trapezoidal sheet is hot-dip zinc-coated steel roll-formed into a trapezoidal profile without paint. Corrosion protection comes entirely from the zinc coating. With no paint cost it is the most economical trapezoidal option and is widely used where appearance is secondary: warehouses, barns, canopies and site buildings.
Galvanized or pre-painted?
- Galvanized: when budget comes first, the building is agricultural, storage or temporary, and no colour is required.
- Pre-painted: when the roof or wall is visible, a corporate colour is wanted, or extra protection over the zinc is needed in corrosive settings such as coastal sites or livestock buildings.
A galvanized surface loses its shine over time and turns matt grey; this is the protective layer formed by zinc corrosion products and is normal.
Coating class sets service life
Outdoor life depends largely on the amount of zinc, given as classes such as Z100, Z140, Z200 and Z275; the number is the total zinc mass on both sides in g/m². For exposed roofs and walls a higher class means longer life. See galvanized coating classes and how long galvanized steel lasts.
Profiles
- 27/200: the most common roof and wall profile, suited to standard purlin spacing.
- 38/151: higher ribs span wider purlin spacing; preferred on industrial and warehouse roofs.
- Corrugated (sinusoidal): the classic wavy sheet, used for fences, canopies and farm buildings.
See trapezoidal sheet sizes and profile types for dimensions, and floor deck sheet for composite slabs.
Storage: avoid white rust
If galvanized bundles stand in the rain or on damp ground, water trapped between sheets forms white rust, a white powdery layer. Store bundles in a dry, ventilated place, raised off the ground and slightly sloped, and cover bundles that will wait for long.
What we need for a quote
Price depends on thickness, coating class, profile, sheet length and total quantity; because steel prices change often, current prices are given as a quote. Please send the thickness, profile, sheet length and quantity (or roof dimensions) and delivery location. Request a quote for galvanized trapezoidal sheet.
Applications
- Warehouse and storage roofs
- Barns, stables and farm buildings
- Canopies and hangars
- Site hoardings and temporary buildings
- Fences and garden walls