WS standing seam roof sheets (Seamlock)

How a standing seam roof works

A standing seam roof has no screws through the sheet. Each sheet is held by concealed clips fixed to the purlins; the side laps of neighbouring sheets are rolled together into a continuous seam with a portable seaming machine, and sealant is injected into the lap. The roof becomes one watertight membrane that can slide on its clips as it expands and contracts.

This makes standing seam the preferred roof for long sheets, low slopes and large industrial and logistics buildings – see our standing seam roof systems article.

Five WS standing seam roof profiles with cover widths and rib heights — WS Seamlock profiles – cover width and rib height in mm.

Profiles and technical data

WS standing seam roof sheets
Code	Cover (mm)	Coil width (mm)	Rib (mm)	Thickness (mm)	Yield	Use
WS 1000-81-3	1000	1200	82	0.47–0.60	G300–450	Roof
WS 1040-70-3	1040	1200	70	0.47–0.60	G300–450	Roof
WS 500-60-2	500	598	60	0.47–0.60	G300–450	Roof
WS 485-65-2	485	1200	65	0.47–0.60	G300–450	Roof
WS 470-81-2	470	595	80	0.47–0.60	G300–450	Roof

The 1000 and 1040 mm profiles have a centre rib and two pans; the 470–500 mm profiles are single-pan sheets for the most demanding wind areas.

Installation sequence

Fix the clips to the purlins along the first sheet line
Lay the sheet, engage the next clip row and the next sheet
Pre-crimp, then close the seam with the seaming machine
Inject sealant in the lap where specified; fix ridge and eave closures and flashings

Clip spacing follows the purlin spacing and the wind design. Use the matching WS clip for each profile – clips are not interchangeable between profiles.

Standards and requirements by market

Codes World Steel designs, fabricates and documents this product to – and the key geometric and load requirements in each market.

United States

ASTM A653 / A792Galvanized / 55 % Al-Zn coated sheet
ASTM A755Coil-coated (pre-painted) metallic-coated sheet
AISI S100Cold-formed steel design
ASTM E1592 · UL 580Wind uplift testing of roof panels

All United States standards →

Australia / NZ

AS 1397Metallic-coated steel sheet – G300 to G550, Z / AZ coatings
AS/NZS 2728Pre-finished / pre-painted sheet
AS 1562.1Design and installation of metal roof and wall cladding
AS 4040Methods of testing sheet roof and wall cladding (incl. cyclonic)

All Australia & New Zealand standards →

Europe

EN 10346Continuously hot-dip coated steel flat products
EN 10169Organic coated (pre-painted) steel flat products
EN 14782Self-supporting metal sheet for roofing and cladding – CE marking
EN 1993-1-3Cold-formed members and sheeting

All Europe standards →

Summary for orientation only – the project specification, the adopted code edition and the authority having jurisdiction govern.

Finishes

Finish	Standards / notes
Zinc-aluminium (AZ) coated	AZ100–AZ150 · AS 1397 / ASTM A792 / EN 10346
Galvanized (Z)	Z180–Z275 · AS 1397 / ASTM A653 / EN 10346
Pre-painted	Polyester or SMP paint system on AZ / Z substrate · AS/NZS 2728 / ASTM A755 / EN 10169
Colours	Standard colour range; special colours on minimum order quantity

Frequently asked questions

Why choose standing seam instead of screw-fixed sheets?

There are no fastener holes in the roof sheet, the seam is continuous and the sheet can move on its clips – a more watertight roof for long sheets and low slopes.

Which profile should I use?

Wide 1000 / 1040 mm profiles cover faster; narrow 470–500 mm single-pan profiles give more clips per square metre for high wind areas. The choice follows the wind design and purlin spacing.

Do you supply the seaming machine?

Seaming is done on site with a portable seaming machine; it can be provided with installation supervision on request.