The extraordinary fiasco surrounding the new Part L building regulations has reached a crescendo this week with a startling new revelation.
Hundreds of copies of the new document, which comes into force today, are in circulation purporting to be the offi cial finalised version; but in fact they contain fundamental inaccuracies, the AJ can reveal.
The version published by privatised government agency, The Stationary Office (TSO), is littered with errors that could wreak havoc with building regulation applications for thousands of projects over the next few months.
Architects and construction professionals who bought the version of Part L from TSO last week should carefully check the details of the document they have procured.
It is understood that the ODPM, which did not sanction the publishing run, is considering legal action against TSO following the mistake.
The company published vast numbers of the 140-page regulations days before the ODPM had signed off the final proof, a mistake that means its version is littered with problems.
The TSO lifted the document from the ODPM website to print, confident that it was correct because it was labelled 'the final version'.
However, this was a mistake by civil servants, and it had not in fact been finalised.
The errors in this version of the document came to light after officers working for RIBA off-shoot the National Building Specification (NBS) visited TSO's offices in Holborn and found the mistakes.
For example, there are two different definitions of how to calculate the extremely important 'simple payback' - recovering the cost of investment of services relating to energy efficiency.
Other errors include the numbering of paragraphs, which could leave architects citing the wrong clauses when making applications.
The NBS, which is the government's official publisher, is furious at this shambles.
Speaking on Tuesday, Steven Cross, the publishing director, said: 'I am surprised at the action taken by TSO and the confusion that this will undoubtedly cause in the marketplace.
'The construction industry is looking for accurate, reliable information that can be used quickly and easily, especially when you consider the extremely short timescales that they have to implement the new regulations.
'The process of refining Parts F and L has been long and tortuous, and has continued to the last minute. The delays have reflected the need to validate the information being supplied.
'I also understand that there are legal implications with regards to TSO's actions and the versions that they have launched, which are being reviewed by government lawyers, ' Cross added.