Fittings
What is a girder coupler?
A girder coupler clamps scaffold tube to the flange of a steel beam. It is how a scaffold is supported from, or tied to, existing structural steelwork.
Use this diagram+
Free to use on your own site, in training material or in a course handout, as long as the credit link stays on it. Paste this where you want the diagram to appear.
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<img src="https://scaffoldoptix.co.uk/glossary/girder-coupler/diagram.svg" alt="girder coupler — scaffold diagram from ScaffoldOptix" width="880" height="620" loading="lazy">
<figcaption>
<a href="https://scaffoldoptix.co.uk/glossary/girder-coupler">What is a girder coupler?</a> — diagram by
<a href="https://scaffoldoptix.co.uk">ScaffoldOptix</a>
</figcaption>
</figure>They are normally used in pairs, one either side of the flange, and they are the standard way of hanging or supporting scaffold from a steel frame rather than from the ground.
This is common on truss-out scaffolds, suspended arrangements and work inside steel-framed buildings, where there is no ground to stand on and the steel is the only thing available.
Fixing to somebody else's structural steel is a design question before it is a fitting question. What the steel can take, and whether the building owner permits it, comes before which coupler is used.
What goes wrong on site
- Clamped to steelwork without anybody establishing what that steel can carry.
- Used singly where a pair is required.
- Fitted to a painted or galvanised flange without allowing for the slip that coating introduces.