Approved Documents L1A, L1B, L2A and L2B - Conservation of Fuel and Power

Approved Document L1A - New Dwellings
(download from Planning Portal)

Approved Document L1B - Existing Dwellings
(download from Planning Portal)

Approved Document L2A - New Buildings Other than Dwellings
(download from Planning Portal)

Approved Document L2B - Existing Buildings Other than Dwellings
(download from Planning Portal)

Approved Document L1A

MAIN CHANGES IN THE 2006 EDITIONS

1. This Approved Document L1 A comes into force on 06 April 2006 in support of the Building and Approved Inspectors (Amendment) Regulations 2006, SI 2006/652. From that date the 2002 edition of Approved Document L1 will become obsolescent. The main changes in the legal requirements and the supporting technical guidance in this edition of Approved Document L1A are as follows.

2. The main legal changes are reproduced at the front of this Approved Document and interleaved as well in the relevant text for ease of reference. In cases of doubt however refer to the SI itself.

3. Part L of Schedule 1 has been consolidated into a single requirement L1, covering all types of building with no limits on application.

4. As well as changes to Part L, there are significant changes to the definitions of works and exempt works, new minimum energy performance requirements, and new requirements for pressure testing, commissioning and energy calculations.

The main legal changes are reproduced at the front of this Approved Document and interleaved as well in the relevant text for ease of reference. In cases of doubt however refer to the SI itself.

5. Four Approved Documents are published reflecting the specialisation in the construction market. In the new Approved Documents regulatory requirements are shown on a green background and defined terms are highlighted. More use has been made of more comprehensive and detailed technical reference publications that therefore form part of the approved guidance. Commentary text has been added in places to explain, for instance, the aims of the guidance and how outcomes are calculated.

6. In this Approved Document the Elemental Method and the Target U-value Method are omitted. There is now only one approach to showing compliance with the energy efficiency requirements. This addresses five criteria:

a. The annual CO, emission rate of the completed dwelling, as calculated using SAP 2005, must not exceed the target set by reference to a notional building.

b. Building fabric and services performance specifications are within reasonable limits.

c. Solar shading and other measures to limit risks of summer overheating are reasonable.

d. Fabric insulation and airtightness, as built, are as intended. More guidance is given on testing the achievement of the intended energy performance including arrangements for pressure testing samples of dwellings. Special arrangements apply in the period up to October 2007 to help in managing dwellings that fail pressure tests.

e. Satisfactory information must be provided enabling occupiers to achieve energy efficiency in use.

7. New technical references from the ODPM give guidance on ways of complying when providing heating and hot water services systems and the benefits of low and zero carbon systems.

8. The technical provisions will mean that higher fabric, heating, ventilation and lighting systems designs will be necessary, delivering an overall improvement of on average 20%.

9. Appendix A contains a new checklist for builders and building control bodies to help in assessing compliance. An example of a completed form is given and an editable blank form can be downloaded from the DCLG web site.

10. Appendix B lists the threshold performance values that if exceeded will cause SAP 2005 approved software to warn of the possibility of failing to comply. Using this facility is not obligatory but it will assist in establishing certainty for builders and building control bodies at the design stage.

11. New competent persons schemes have been approved for pressure testing and energy performance calculations, the scope of the existing schemes has been widened, and more scheme operators have been approved. Engaging an approved Competent Person is not obligatory but building control bodies are authorised to accept self-certification by such persons enabling reduced administrative burdens, delays and costs.

Approved Document L1B

MAIN CHANGES IN THE 2006 EDITION

1. This Approved Document L1B comes into force on 06 April 2006 in support of the building and Approved Inspectors (Amendment) Regulations 2006, SI 2006/652. From that date the 2002 edition of Approved Document L1 will become obsolescent. The main changes in the legal requirements and the supporting technical guidance in this edition of Approved Document L1B are as follows.

   Changes in the legal requirements

2. The main legal changes are reproduced at the front of this Approved Document and interleaved as well in the relevant text for ease of reference. In cases of doubt however refer to the SI itself.
3. Part L of Schedule 1 has been consolidated into a single requirement L1, covering all types of building with no limits on application.
4. As well as changes to Part L, there are significant changes to the definitions of works and exempt works and a new definition of ‘thermal element’ is introduced to address more types of alteration and renovation work. New requirements apply when providing or renovating thermal elements and commissioning heating, ventilation and lighting systems.
5. The scope of the Competent Persons schemes in Schedule 2A has been widened and more scheme operators have been approved. Engaging an approved Competent Person is not obligatory but building control bodies are authorised to accept self-certification by such persons enabling reduced administrative burdens, delays and costs.
6. The list of works in Schedule 2B that need not be notified to building control bodies (but which must still comply) has been substantially increased to include minor works on heating, ventilation and lighting systems.

   Changes in the technical guidance

7. Four Approved Documents are published reflecting the specialisation in the construction market. In the new Approved Documents regulatory requirements are shown on a green background and defined terms are highlighted. More use has been made of more comprehensive and detailed technical reference publications that therefore form part of the approved guidance. Commentary text has been added in places to explain, for instance, the aims of the guidance and how outcomes are calculated.
8. In this Approved Document the guidance is based on an elemental approach to compliance. The main technical changes comprise a general improvement in the performance standards that are considered reasonable for work on thermal elements, windows, doors, heating, hot water, ventilation and lighting systems in existing dwellings. As an exception to this the standards for replacement windows, roof windows and rooflights are unchanged from those in ADL1 (2002).
9. More guidance is given enabling greater flexibility when building extensions including conservatories and other highly glazed designs. The exemption for conservatories remains unchanged.
10. A new section contains guidance on ways of complying with the new requirements for provision and renovation of thermal elements. A new Appendix A gives examples of what can be achieved cost-effectively.

Approved Document L2A

MAIN CHANGES IN THE 2006 EDITIONS

1. This Approved Document L2A comes into force on 06 April 2006 in support of the Building and Approved Inspectors (Amendment) Regulations 2006, SI 2006/652. From that date the 2002 edition of Approved Document L2 will become obsolescent. The main changes in the legal requirements and the supporting technical guidance in this edition of Approved Document L2A are as follows.

   Changes in the legal requirements

2. The main legal changes are reproduced at the front of this Approved Document and interleaved as well in the relevant text for ease of reference. In cases of doubt however refer to the SI itself.
3. Part L of Schedule 1 has been consolidated into a single requirement L1, covering all types of building with no limits on application.
4. As well as changes to Part L, there are significant changes to the definitions of works and exempt works, new minimum energy performance requirements, and new requirements for pressure testing, commissioning and energy calculations.

   Changes in the technical guidance

5. Four Approved Documents are published reflecting the specialisation in the construction market. In the new Approved Documents regulatory requirements are shown on a green background and defined terms are highlighted. More use has been made of more comprehensive and detailed technical reference publications that therefore form part of the approved guidance. Commentary text has been added in places to explain, for instance, the aims of the guidance and how outcomes are calculated.
6. In this Approved Document the Elemental, Whole Building and Carbon Emissions Calculation Methods are omitted. There is now only one approach to showing compliance with the energy efficiency requirements. This addresses five criteria:

1. The annual CO2 emission rate of the completed building, as calculated using an

   Approved calculation tool, must not exceed the target set by reference to a

   notional building. The approved calculation tools comprise the Simplified

   Building Energy Model (SBEM) or approved commercial software.

2. Building fabric and services performance specifications are within reasonable

   limits.

3. Non-air-conditioned buildings will not cause high internal temperatures in

   summer as a result of excessive solar gains. (Solar performance of air- conditioned buildings is taken into account in the CO2 calculations).

4. Fabric insulation and airtightness, as built, are as intended. More guidance is

   given on testing the achievement of the intended energy performance including

   arrangements for obligatory pressure testing in most circumstances. Special

   arrangements apply in the period up to October 2007 to help in managing

   buildings that fail pressure tests.

5. Satisfactory information must be provided enabling occupiers to achieve energy

efficiency in use.

1. New technical references from the ODPM give guidance on compliance regarding the use of the calculation tools, ways of complying when providing heating, cooling and ventilation systems, and the benefits of low and zero carbon systems.
2. The technical provisions will mean that higher performance fabric, heating, ventilation, air conditioning and lighting systems designs will be necessary. For buildings that are naturally ventilated and heated the improvement will be around 23%. For air-conditioned buildings the improvement will be around 28%.
3. The standard of improvement has been set so flat. Low and zero carbon energy sources will have attractions in many cases.
4. Appendix A contains a new checklist for builders and building control bodies to help in assessing compliance. An editable blank form can be downloaded from the ODPM web site.
5. New competent persons schemes have been approved for pressure testing and energy performance calculations, the scope of the existing schemes has been widened, and more scheme operators have been approved. Engaging an approved Competent Person is not obligatory but building control bodies are authorised to accept self-certification by such persons enabling reduced administrative burdens, delays and costs.

Approved Document L2B

MAIN CHANGES IN THE 2006 EDITION

1. This Approved Document L2B comes into force on 06 April 2006 in support of the Building and Approved Inspectors (Amendment) Regulations 2006, SI 2006/652. From that date L2 will become obsolescent. The main changes in the legal requirements and the supporting technical guidance in this edition of Approved Document L2B are as follows.

   Changes in the legal requirements

2. The main legal changes are reproduced at the front of this Approved Document and interleaved as well in the relevant text for ease of reference. In cases of doubt however refer to the SI itself.
3. Part L of Schedule 1 has been consolidated into a single requirement L1, covering all types of building with no limits on application.
4. As well as changes to Part L, there are significant changes to the definitions or works and exempt works and a new definition of ‘thermal element’ is introduced to address more types of alterations and renovation work.
5. New requirements apply when providing or renovating thermal elements and the commissioning of heating, ventilation and lighting systems.
6. A further new requirement requires the improvement of the energy performance of buildings with floor areas over 1000m² as a consequence whenever these buildings are subject to major works.
7. The scope of the Competent Persons schemes in schedule 2A has been widened and more scheme operations have been approved. Engaging an approved Competent Person is not obligatory but building control bodies are authorised to accept self-certification by such persons enabling reduced administrative burdens, delays and costs.
8. The list of works in Schedule 2B that need not be notified to building control bodies (but which must still comply) has been substantially increased to include minor works on heating, ventilation and lighting systems.

   Changes in the technical guidance

9. Four Approved Documents are published reflecting the specialisation in the construction market. In the new Approved Documents regulatory requirements are shown on a green background and defined terms are highlighted. More use has been made of more comprehensive and detailed technical reference publications that therefore form part of the approved guidance. Commentary text has been added in places to explain, for instance, the aims of the guidance and how outcomes are calculated.
10. In this Approved document the guidance is based on an elemental approach to compliance. The main technical changes comprise a general improvement in the performance standards that are considered reasonable for thermal elements, windows, doors, heating, hot water, cooling, mechanical ventilation and lighting systems provided, or replaced as part of work in existing buildings. As an exception to this the standards for replacement windows, roof windows and rooflights are unchanged from those in ADL2 (2002).
11. A new section gives guidance on complying with the new requirement to make cost-effective consequential improvements whenever work is carried out on larger buildings.
12. More guidance is given enabling greater flexibility when building extensions including conservatories and other highly glazed designs. The exemption for conservatories remains unchanged.
13. A new section contains guidance on ways of complying with the new requirements for provision and renovation of thermal elements. Cost-effectiveness for these purposes is defined as showing a simply payback period not exceeding 15 years. A cross-reference is given to Appendix A in ADL1B for examples of what can be achieved cost-effectively.