Central Heating News

Central Heating News

Changes to Building Regulations Part L 2010

(April 26, 2011)

From 1 October 2010, the Building Regulations – Part L is changing.

  • SEDBUK banding (eg Band A or Band B) disappears and is replaced with minimum % efficiency figures
  • Gas boiler efficiency will be listed on either SEDBUK 2005 or SEDBUK 2009 lists
  • Only gas boilers with an efficiency of 90% or above (SEDBUK 2005, previously known as SEDBUK Band A) can be installed.  If using SEDBUK 2009 data, the minimum efficiency is 88%

Changes to SEDBUK

According to the Domestic Building Service Compliance Guide that accompanies Part L, the terms Band A, Band B etc will be dropped from 1 October 2010 to avoid confusion when the forthcoming Energy using Products directive (EuP) is introduced.

EuP will measure the energy efficiency of systems and will provide a label similar to the current Energy Efficiency rating labels currently seen on washing machines and refrigerators.

The new SEDBUK 2009 ratings will take account of summer and winter seasonal efficiency, predominantly from hot water production, rather than be calculated at just one point through the year.  This will reduce the overall efficiency by around two per cent.

So, for example, a current SEDBUK Band A boiler will either be SEDBUK 2005 90.1% or SEDBUK 2009 88.1%, depending on what the manufacturer states, in line with Standard Assessment Procedure (SAP).  If the efficiency is not stated as SEDBUK 2009, it will be assumed to be SEDBUK 2005.

All boilers must now be SEDBUK 2005 90% or SEDBUK 2009 88%

Until the changes to Part L in October 2010, it has been possible to fit SEDBUK 2005 Band B boilers.  This clause has now been removed, and from 1 October 2010, all boilers must now be the equivalent of SEDBUK 2005 Band A, with a minimum efficiency of 90%.  This applies to existing dwellings as well as newbuild, and effectively outlaws the installation of anything other than SEDBUK 2005 Band A appliances.


Where building work has started before 1 October 2010, boilers equivalent to SEDBUK 2005 Band B may still be installed as planned.

If a contract for work has been agreed before 1 October 2010, the installation of boilers equivalent to SEDBUK 2005 Band B may continue or be carried out, provided the work is completed by 6 April 2011.

Where a building notice, an initial notice, a plans certificate and amendment notice or a public body’s notice has been given or full plans submitted before 1 October 2010, the work or fitting of boilers equivalent to SEDBUK 2005 Band B may be carried out, provided the work is completed before 6 April 2011.

Hot water storage

Changes have also been made to domestic hot water storage vessels to reduce the standing losses by over 10%.  This will reduce the carbon emissions associated with domestic hot water storage.