BCSA publishes latest NSSS edition

The 6th edition of the NSSS is an invaluable tool for specifiers and designers of steel structures

The British Constructional Steelwork Association [BCSA] has published the 6th Edition of the National Structural Steelwork Specification [NSSS] for Building Construction (BCSA Publication No. 57/17).

The 6th edition can be used for all types of building construction designed for static loading and is based on Execution Class 2 structural steelwork designed in accordance with BS 5950-1 or BS EN 1993-1-1 (including BS EN 1993-1-8 and BS EN 1993-1-10) and executed in accordance with BS EN 1090-1 and BS EN 1090-2.

BCSA Director of Engineering Dr David Moore said: “The NSSS clarifies and aids the process of translating designers’ requirements into specific work instructions for execution. Specifiers are encouraged to use this latest NSSS as the default specification for all steel building structures.”

The main changes between the 5th edition (CE Marking version) and the latest 6th edition are:

• Various clauses throughout the NSSS have been modified to make it clear that under the Construction (Design and Management) Regulations 2015 all parties have a duty to cooperate with others involved in the construction of the works.
• Information is increasingly exchanged in electronic format and on government projects Building Information Modelling (BIM) is mandatory. Additional definitions for terms used in BIM have been added and Sections 1 and 3 of the NSSS have been updated to include the BIM information required and provided by the steelwork contractor.
• UK suppliers and distributors of structural fasteners shall comply with National Highways Sector Scheme 3 (NHSS3) or an equivalent quality management system
• BS EN 1993-1-10 ‘Design of steel structures. Part 1.10 Material toughness and through-thickness properties’, allows fracture mechanics to be used to determine toughness requirements. This approach has been included in Section 2.2.5 as an alternative to selecting the steel qualities according to Table 2.2.
• The tables for specifying ordinary and preloaded bolt assemblies have been updated and include additional tables for ordinary tie-bar assemblies and matching ordinary tie- bar assemblies.
• Clause 4.1.1 on the traceability of steel products and in particular the meaning of ‘Partial’ traceability has been clarified
• A new Clause 4.11 has been added which describes the method for adding together permitted deviations.
• Clause 5.3.2 has been modified to allow the Responsible Welding Coordinator to act as the examiner/examining body for the approval of welding procedures provided suitable competence can be demonstrated.
• Clause 5.6 on the welding of shear studs has been revised and includes requirements for initial type testing and routine testing.
• A new Clause 11.5 on modifications has been added to make it clear that any proposals to improve or modify the work shall be considered and confirmed by the engineer prior to the modifications being carried out.
• References to British Standards (issued with BS, BS EN, BS EN ISO or BS ISO references) have been updated throughout the specification.

Copies of the National Structural Steelwork Specification for Building Construction 6th Edition (BCSA Publication No. 57/17) can be obtained from BCSA’s web site (www.steelconstruction.org/shop) at a cost of £20 + VAT for Non-members and £15 + VAT for BCSA members. This book is only available in PDF format.