Thermal requirements revised

Government announces updates to building regulations effective from October 2013 and April 2014

The Government has published details of revisions to the Building Regulations for England to be implemented in October 2013 and April 2014.

The changes focus on Part A (Structure) and Part C (Site preparation and resistance to moisture) as well as giving details of the next steps towards zero carbon homes with Part L (Conservation of fuel and power).

Part A (structure)

The Approved Document is being updated to contain reference to the latest British Standards which are based on Eurocodes. To support this the Government will also be publishing additional guidance on:

  • How withdrawn standards may still be used for some time giving industry time to adapt
  • How BCBs and Engineers may continue to accept old design standards for smaller scale work for the foreseeable future.

There are also other minor changes made to align guidance for strip foundations in shrinkable clay soils and the recovering of roofs with common practice.

Part C (Site preparation and resistance to moisture)

Information relating to the requirement for Radon protection measures is being updated to reflect the 2007 mapping by Public Health England and updated references to BRE publication BR211 'Radon'.

(There will be no change for homebuilders building in accordance with NHBC Standards as the standards have required homes to be built to these maps for some time). The references to the new structural design British Standard for geo-technics in the site investigation of sites will also be updated.

The updated Approved Document for Parts A and C - in force on 1 October 2013.

Part L (Conservation of fuel and power)

The changes to Part L will now come into force in April 2014 and will set a requirement for new homes to achieve a 6% carbon improvement on 2010 Regulations across the build mix. This is slightly lower than the 8% target originally put forward as the Government's preferred option when it consulted in 2012. House builders will continue to have flexibility in how they approach carbon targets but, keeping a focus on the building fabric, a fabric energy efficiency target will be introduced. There is also a target of 9% improvement on Part L 2010 for commercial buildings. The Government also announced that it would shortly be consulting on the next steps to Zero Carbon Homes and also on delivering Allowable Solutions.

In summary the headline changes are:

  • Projected £16m savings per annum to business
  • 6.4 million tonnes CO2 saved per annum

New homes:

  • 6% improvement on Part L 2010 across the build mix
  • Emphasis on building fabric with the introduction of a fabric energy efficient target (FEES)
  • No QA process for the building of new homes instead the Government are investing in a project looking at the performance gap through the Zero Carbon Hub

Non domestic:

  • 9% improvement on Part L 2010 across the build mix
  • Minimum energy efficiency targets for air conditioning and lighting replacements

Preview part L updates - 2014

Part L 2013

Following the consultation documents, DCLG has release the new Approved Documents now on the Planning Portal - to support Part L changes, which become effective from 6 April 2014.

The following provides a brief summary of the main changes.

Existing dwellings

There is good news for existing homeowners, as there are no proposed changes to energy efficiency standards for works on existing dwellings. Other than some minor modifications to aid clarity and provide flexibility, loft conversions and extensions can continue to use the standards detailed in the 2010 edition of Part L.

New housing

The proposed changes are equivalent to a 6% improvement, and concentrate on performance of the fabric.

The recipe for compliance will be essentially a Target Fabric Energy Efficiency (TFEE) rate coupled with a Target CO2 Emission Rate (TER)

In addition, an 'elemental recipe' approach will be included, which in itself will provide a compliant solution. It may not be the most cost effective for everyone but it might make the task of compliance easier for some buildings. DCLG stress this is not a return to a more prescriptive approach, more a robust starting point for compliance.

As part of the commitment to take a sensible cost effective step towards zero carbon homes in 2016 existing fuel factors will be retained in line with the current requirements and there are some relaxed requirements for fabric performance for detached dwellings.

Non-domestic building

An aggregate 9% CO2 target uplift is proposed, with more onerous targets set for building types such as schools, offices and hotels. Again the focus will be on improving fabric performance and tightening controls on items like chillers and lighting, although for lighting there will be the option of using the Lighting Energy Numeric Indicator as a method of demonstrating compliance.

So what to look out for in the coming weeks:

  • L1A and L2A - new approved documents due for release on 22 October, which will include a summary of notional buildings
  • Library of advanced construction joint details - should be available before
  • 6 April 2014
  • L1B and L2B - amendments to 2010 document on points of clarification only
  • Building services compliance guides - new versions to be released to support new Approved Documents
  • SAP - updated to generate TER and TFEE
  • SBEM - to include new notional building and introduction of formal SBEM Appendix Q framework

Transitional arrangements

The new Regulations come into effect on 6 April 2014. Applications submitted after this date will need to comply with the new standards.

For applications made before 6 April 2014, the current 2010 standards can be used, with the requirement - start works within 12 months.

Last updated: Tuesday, 11 February, 2020.