Through-Deck Stud Welding – What It Is and Why It Matters in Composite Floors

In modern composite floor construction, through-deck stud welding (TDSW) is the gold standard for achieving structural composite action between steel beams and concrete slabs. It is fast, efficient, and critical to the load-bearing capacity of your structure. At RMD Profiles, we not only supply decking but offer stud welding services as part of our Supply & Fix package, using fully trained teams and SCI-compliant procedures.

What Is Through-Deck Stud Welding?

Through-deck stud welding of shear studs on a steel beam

Headed shear studs welded through the steel deck

It involves welding headed shear studs directly through the steel deck into the top flange of the beam. Once the concrete is poured, the stud anchors the slab to the beam, allowing them to act together. This is what gives composite slabs their strength.

Components:

Studs: typically 19mm diameter
Hilti or Nelson equipment
Deck: MetFloor 55, 60, 80, or ComFlor 46, 51, 60, 80 profiles
Welding gun, power supply, ceramic ferrules
300 kVA generator mounted on the back of an 18t unit

Why It’s Used

✅ Shear transfer between slab and beam.
✅ Faster construction, with no need for pre-studded beams.
✅ Greater structural economy, smaller beams for the same span.
✅ SCI Code P300 and BCSA compliant method.
✅ Works with FibreDeck or mesh as transverse reinforcement.

Through-deck stud welding equipment on site

Installation Best Practice

From SCI P300 and the BCSA Code of Practice:

Studs must penetrate the decking ribs properly.
Weld quality should be visually inspected and bend tested.
Beams must be free from paint or galvanisation at weld points.
Welds must be carried out by trained operatives with CSCS and SSSTS.

At RMD, we carry out:

On-site ring and bend tests
Welding to BS EN ISO 14555 standards
Inspection logs and traceability
Service across the UK with reliable teams

When Is Stud Welding Required?

Composite floor deck ready for through-deck stud welding

✔ Composite floor design using MetFloor, SMD or TATA ComFlor.
✔ Where slabs and beams are designed to work compositely.
✔ Where FibreDeck is used in place of mesh.
✔ Projects needing SCI or Eurocode compliance.

Avoid this if:

🚫 You are using non-composite beams.
🚫 The decking is temporary sacrificial formwork only.

Through-deck stud welding is not optional for composite floors, it is foundational, and it has to be done right. With RMD you get fully compliant stud welding, complete with traceability and safety procedures, delivered through our stud welding service. Want a quote? Upload your steel GA or DWG and we will do the rest.