BS EN Eurocodes – The implications of use with withdrawn BS Standards
To members of CB/20 and B/525 Eurocodes committees for dissemination:
Following a number of requests for clarification on the subject of structural designs which use both BS EN Eurocodes and the now withdrawn British Standard design codes, CB/20 Advisory committee for Structures discussed this at their last meeting on 9 November 2010. Following these discussions the Chairman has asked me to forward the following comments for dissemination:
On 31 March 2010 BSI withdrew the UK Standards which conflict with the Eurocodes as required under the agreement between National Standards Bodies and CEN. At that time the Eurocodes, including the National Annexes needed to support their use, were mostly completed and published in the UK. There have been a few outstanding UK National Annexes that have been published subsequently.
The Department of Communities and Local Government has advised via its Circular Letter of 29 January 2010 of the availability of the Eurocodes and associated UK National Annexes for the design of building structures in England and Wales, (Ref: 1)
Incorporation of the Eurocodes as references into Approved Document A to the England and Wales Building Regulations is being considered as part of a wider Building Regulations review that is now underway and is planned to complete by 2013.
In Scotland the Technical Handbooks to the Building Standards were reissued on 1 October 2010 and include references to the Eurocodes. The Building Regulations supporting technical guidance for Northern Ireland are currently in the course of review and consultation and are likely to consider inclusion of the Eurocodes as referenced Standards.
In this period, while the use of the Eurocodes is progressing in the UK, questions have been raised on the suitability of using combinations of Eurocode parts or rules within them with parts of the withdrawn British Standards. The drive for this can come from design information in organisations that are not yet updated to Eurocode requirements or from designers who still continue to use the withdrawn standards but wish to take information from the Eurocodes.
Designers should be aware however that the Eurocode package is complete and there should be no technical reason why the design rules in the Eurocodes need to be augmented by the use of withdrawn British Standards.
BSI has no part in the process of building regulations approvals but it must be emphasised that the Eurocodes contain the latest technical information and its Committees are actively engaged in responding to questions, clarifying uncertainties and in maintenance of the Eurocode suite of standards. No further work is being conducted on the withdrawn BS Standards.
Clearly a design which complies with the Eurocodes can be considered as Eurocodes compliant. BSI cannot support users who use a design combination of Eurocodes and withdrawn British Standards. If approaches of this kind are put forward by industry groups or others then it is recommended that supporting justification should be made available to potential users and to checking authorities and bodies. It is clearly the responsibility of users to make necessary calculations and checks to ensure that the final design fulfils all its requirements including those under building regulations.
I hope this clarifies the matter.
Committee Manager CB/20
Ref 1: http://www.communities.gov.uk/documents/planningandbuilding/pdf/1454859.pdf