Part L - Conservation of fuel and power

Information is available from the Communities and Local Government website (external link).

There are four main aspects to this part:

• L1A Work in new dwellings
• L1B Work in existing buildings (this document only relates to dwellings)
• L2A Work on new buildings other than dwellings
• L2B Work on existing buildings that are not dwellings
  

1. L1A - The method of complying with the thermal requirements will be based on carbon emissions rate against a specified target. The elemental method of compliance will no longer be permitted. The objective is to improve robustness and air tightness with possible sample air testing, the use of technologies is recognised such as solar power;
2. L1B - It is intended to improve the existing housing stock with the introduction of specified U values to be achieved when replacing elements of structure such as wall, floors or roof or if a thermal element is retained/renovated;
3. L2A - The elemental approach has been removed and replaced with a notional calculation methodology. This determines the C02 emissions from a notional building of the same shape and size. The emissions target for the actual building is then derived by reducing the emissions calculated for the national building by using improvement factors.
4. L2B - The document introduces concepts for improving the energy efficiency of the building as a whole and controlled elements similar to document L1B.

The 2006 editions of the Part L Approved Documents present new methods to demonstrate compliance with the Building Regulations. In particular, there is a shift in emphasis away from pure energy conservation towards Carbon Dioxide emission reduction

Target CO2 Emission Rate (TER)

The TER is the minimum energy performance requirement for new buildings and large extensions and is calculated in accordance with methodology approved by the Secretary of State using either of the two calculation tools listed below. The TER provides the target that the proposed building or extension must meet.

The two calculation tools are:

• the Government's Standard Assessment Procedure (SAP2005) (external link) - for individual dwellings under 450 square metres total floor area; and
• the Simplified Building Energy Model (SBEM) (external link) - for dwellings with more than 450 square metres total floor area and for buildings other than dwellings.

Dwelling Emission Rate (DER) or Building Emission Rate (BER)

To assess compliance with the Building Regulations the TER must be compared to either the DER or BER calculated for the proposed building.
Confirmation of the TER and DER or BER is needed at both the design stage and at completion and an accredited person must compile them. The terms TER, DER and BER are fully explained in the Approved Documents.

Other Requirements

In addition to the aspects listed earlier, because the Government also wants to improve the existing building stock, for the first time, where alterations and extensions significantly affect an existing building, it will normally be the case that the upgrading of the existing building will be required.

Transitional Arrangements

The Government has tightened the time for the building industry to comply with new climate change regulations, Housing and Planning Minister Yvette Cooper announced.

Transitional arrangements have been cut from the usual maximum of three years to just 12 months to speed up take up of the regulations to maximise their impact on climate change.  All new buildings without full building plans approved by 6 April 2006 must comply with the new Part L building regulations from 6 April 2006, which increase the energy efficiency of new buildings by 20 per cent from April, and by 40 per cent since 2002.  These regulations have already been brought in two years ahead of schedule.

Yvette Cooper said:

"Tackling climate change is one of the biggest long-term challenges we face. That is why on this occasion we need the building industry to comply with the new regulations much more rapidly than normal.

These new regulations, combined with those in 2002, deliver a 40 per cent increase in energy efficiency standards in just four years, and cut householders' fuel bills too."

The normal transitional arrangements for new building regulations last for up to three years. The last time that Part L was updated in 2002 the building industry had three years from the lodging of plans in which to commence work under the transitional arrangements.

Building work which has already received full building plans approval where work has not yet started will need to begin before 1 April 2007 rather than the usual three year period in order to be covered by the transitional arrangements this time.

Smaller building works that have not started before 6 April 2006 which do not require full building plans approval will need to comply straight away unless contracts have already been signed.

Where contracts have been entered into before 6 April 2006, they will need to commence work within 6 months to be covered by the transitional arrangements. This will ensure that smaller builders and householders who may not be fully aware of the technical changes are not unreasonably affected.

Notes to editors:

1. The revised Part L 2006 regulations come into effect from 6 April 2006. From that date any building work must comply with the revised Part L 2006 regulations unless:

• Work has started before 6 April 2006 in accordance with a building notice, full plans, initial notice or amendment notice.
• Where full plans are not required to be deposited, a contract is entered into before 6 April 2006, provided that the work is started before 1 October 2006.
• Full plans have been deposited and approved before 6 April 2006, provided that work is started before 1 April 2007.
• A plans certificate or plans certificate combined with an initial notice has been given to a local authority before 6 April 2006, provided that the work is started before 1 April 2007.

2. Any building work carried out under the transitional arrangements will be subject to the current Part L (2002) regulations and energy efficiency standards.

3. Amendments to Parts L (Conservation of Fuel and Power) and F (Ventilation) of the Building Regulations were announced on 13 September 2005. These changes are being implemented together because they are closely linked and to help the industry to comply with the changes.

4. The amendments raise the energy performance of new building by 20 per cent for dwellings and up to 27 per cent for other buildings. Taking account of changes already made in 2002 energy efficiency standards will have been raised 40 per cent over four years.

5. The implementation date for the revised Part L regulations has been brought forward from the spring of 2008 as previously stated to April 2006 to increase their contribution to tackling climate change.

6. The revisions to Part L to be implemented in April 2006 will set maximum carbon dioxide emissions for whole buildings. This performance-based approach will offer designers the flexibility to choose solutions that best meet their needs, and that are cost-effective and practical. However, the revisions to Part L will raise performance standards to a level that will provide a strong incentive to designers to consider Low and Zero Carbon systems.