Steel Beam Marking: Pop Marks, Erection Marks and CE Marks

A fabricated steel beam leaves the workshop carrying several different marks, each meant for a different reader: the fabricator setting out holes and cuts, the erector putting the piece in the right place, and the engineer or building control checking that the steel is what was specified. Here's what each one is.

Pop marks: setting-out marks

Pop marks are small dots punched into the steel with a centre punch when it's marked out by hand. They show where a hole is drilled, where a cut line runs, or where a cleat or plate sits on the beam.

They're used because they last. Chalk and paint rub off or burn off, but a punched dot stays in the steel through handling, cutting and welding. Where steel is drilled and cut by machine straight from the 3D model, fewer hand pop marks are needed. On hand-marked work they're still the standard way to set out.

Erection marks: which piece goes where

Every fabricated member gets a unique erection mark (also called a piece mark), such as B1, C4 or R2. The same mark appears on the erection drawings, so whoever is fitting the steel can match each piece to its position without guessing.

The mark is usually painted or written near one end. Where it matters which way round a piece goes, there's often an orientation mark too, showing which end is which or which face is the top.

On galvanised steel, paint marks don't survive the galvanising process, so marks are hard-stamped into the steel or put on a metal tag instead.

Material and traceability marks

Steel arrives from the mill with markings that link it to its inspection certificate, which records the grade and test results for that batch. Fabricators keep that link as the steel is cut into pieces, so a finished beam can be traced back to the certificate for the steel it came from. How strictly this is done depends on the execution class: at the higher classes, full traceability is required.

CE and UKCA marking

The CE or UKCA mark is a different kind of marking. It isn't a stamp on each beam that tells you where it goes. It's the fabricator's declaration that the steelwork conforms to EN 1090-1, made by a fabricator certified to do so, and it's normally carried on the label and documents that come with the steel. Our EN1090 and CE / UKCA marking guide explains what it covers.

Why it matters on site

Most marking problems show up during erection: two similar beams fitted in each other's places, or a beam fitted the wrong way round, so its connections or stiffeners end up in the wrong spot. A few habits avoid that:

• Check each erection mark against the drawing before lifting the piece into place.
• Don't grind, paint or plaster over marks before the steel has been checked and signed off.
• Keep the delivery paperwork, as it's what links the steel back to its certificates.

Frequently asked questions

What does a pop mark look like? A small dimple, a millimetre or two across, punched into the surface. You'll often see a row of them along a line, or one at the centre of each hole position.

Will the marks show through the paint? Painted erection marks are usually covered by the finish. A punched dot can show as a slight dimple. On exposed architectural steel, say so at the start and the marks can be kept to faces that won't be seen.

Do domestic beams get marked too? Yes, though on a single beam for a house the mark may simply identify the beam and which end is which. On a job with several beams and posts, each piece gets its own mark to match the drawing.

Need beams, posts or a full frame made to your engineer's drawing? See our structural steelwork service or send us the drawing.