Skip to content Skip to footer

The 2014 Part L of the Building Regulations – here at last

Share on facebook
Share on twitter
Share on linkedin

After a long wait, the 2014 Approved Documents L1A and L2A have arrived, providing guidance on Conservation of Fuel and Power in new buildings. However, as with previous changes, the 2010 documents continue to apply to projects where work started or an application was made before that date.


BSRIA’s Building Regulations training will update you on all the changes that will come into effect on 6 April 2014.

The most noticeable change for new dwellings is a requirement to calculate the fabric energy efficiency. This is in addition to calculating CO2 emissions, which has been a requirement since 2006. Fabric energy efficiency is measured in kWh per square metre of floor area, and takes into account the space heating and cooling demand. The CO2 emissions, on the other hand, are measured in kg of CO2 per square metre of floor area and the calculation only takes cooling into account for dwellings that use mechanical cooling. To achieve compliance, both the fabric energy efficiency and CO2 emissions must be below those of a notional dwelling. This notional dwelling has been redefined such that an emissions reduction of 6% is achieved, compared with dwellings that meet 2010 standards.

The methods of compliance for new non-dwellings have not changed significantly, however the CO2 emissions reduction is greater than for dwellings: 9%. This means more energy efficiency measures will need to be incorporated, and even though renewables are not a requirement, more designs may incorporate them as a means of achieving the CO2 target. Some of the minimum plant efficiencies, set out in the Non-domestic Building Services Compliance Guide have been upgraded – for example the minimum efficacy of lighting in office, industrial and storage areas has been upgraded from 55 to 60 luminaire lumens per circuit-watt.

Changes to the Approved Documents for existing buildings – L1B and L2B – are minimal. So much so, that they have been issued as an amendment slip. We are, however, assured that consolidated versions of these Approved Documents will be issued before they come into effect on 6 April.

BSRIA runs Building Regulations training courses – Introduction to the Building Regulations next runs on 12 March, and Understanding Parts L & F next runs on 25 February. Any of our courses can be run in-company and customised to meet the needs of your staff. For more information go to

Show CommentsClose Comments

Leave a comment