DCLG has just published the revised 2013 versions of the following documents on the planning portal;
Part L 2013 changes
Approved Document L - Conservation of fuel and power
Building Services Compliance Guides
These will come into effect from 6th April 2014. The same 12 month transitional arrangements are in place as those used for the last set of changes to Part L back in 2010.
Minor amendments to the 2010 versions of ADL1B and ADL2B to update references to third party guidance will follow next week.