Steel Fabrication Specification: What Standard Are Beams Built To?

All structural steelwork designed by PorthouseDean must be fabricated and erected in accordance with the National Structural Steelwork Specification (NSSS).

What Is the NSSS?

The National Structural Steelwork Specification is the definitive UK standard for the fabrication and erection of structural steelwork. It is published by the British Constructional Steelwork Association (BCSA) and sets out:

– Material standards — steel grades, testing requirements and product certification
– Fabrication tolerances — how accurately holes must be drilled, how straight elements must be and how welds must be prepared
– Inspection and testing — what quality checks must be carried out and documented
– Erection requirements — how steelwork should be handled, stored and installed on site

The NSSS is the standard that steel fabricators in the UK work to as a matter of course. Specifying it ensures the steelwork your builder receives is fit for purpose and that the fabricator has taken responsibility for meeting the quality requirements.

Why Fabrication Drawings Must Be Approved First

Before a fabricator begins manufacturing any steelwork for a PorthouseDean project, they must submit their workshop drawings to PorthouseDean for review and approval.

This step is essential because structural drawings communicate design intent, while fabrication drawings are the detailed production documents. Errors introduced at the fabrication drawing stage — wrong connection geometry, incorrect bolt holes, wrong plate sizes — can result in steelwork that does not meet the structural design and cannot be safely installed.

The engineer’s review catches these issues before steel is cut, not after.

What Clients Need to Know

As a client, you do not need to manage this process directly — it is between your contractor, the fabricator and PorthouseDean. However, you should be aware that:

– Fabrication cannot legitimately begin without approval of workshop drawings
– Rushing this stage to save time on the programme creates risk and is not recommended
– Where the fabrication review falls outside PorthouseDean’s standard scope, a fee may apply

If your contractor is pressing to begin fabrication before drawings are approved, please ask them to contact PorthouseDean first.

Questions?

Get in touch with PorthouseDean if you have questions about the fabrication process for your project.