Appendix A: Key terms

NOTE: Except for the items marked * (which are from the Building Regulations 2010), these definitions apply only to Approved Document L, Volume 1: Dwellings.

Air barrier An air barrier controls air leakage into and out of the building envelope. This is usually in the form of a membrane.

Air permeability The measure of airtightness of the building fabric. It is defined as the air leakage rate per hour per m2 of envelope area at the test reference pressure differential of 50Pa or 4Pa.

• The limiting air permeability is the worst allowable air permeability.

• The design air permeability is the target value set at the design stage.

• The assessed air permeability is the value used in establishing the building emission rate and the building primary energy rate. The assessed air permeability is based on a measurement of the air permeability of the building concerned.

Airtightness The resistance of the building envelope to infiltration when ventilators are closed. The greater the airtightness at a given pressure difference across the envelope, the lower the infiltration.

Automation A control function which automatically adjusts time and temperature settings based on occupancy detection and/or stored data from user adjustments over time.

Benchmark Commissioning Checklist A checklist that can be used to show that commissioning has been carried out satisfactorily. (Benchmark is registered as a European Collective Mark by the Heating and Hot Water Industry Council, and the content is copyright.)

Building automation and control system A system comprising all products, software and engineering services that can support energy efficient, economical and safe operation of heating, ventilation and air conditioning systems and on-site electricity generation through automatic controls and by facilitating the manual management of those building
systems.

Building control body A local authority building control department or an approved inspector.

**Building envelope*(in relation to a building) Defined in regulation 35 as the walls, floor, roof, windows, doors, roof windows and rooflights.

Centre pane U-value The U-value determined in the central area of the glazing unit, making no allowance for edge spacers or the window frame.
**Change to energy status* Defined in regulation 2(1) as any change which results in a building becoming a building to which the energy efficiency requirements of these Regulations apply, where previously it was not.

Circuit-watt Refers to the power consumed in lighting circuits by lamps and, where applicable, their associated control gear (including transformers and drivers) and power factor correction equipment.

Coefficient of performance (COP) A measure of the efficiency of a heat pump at specified source and sink temperatures, measured using the procedures in BS EN 14511-2.

• Heating COP = heat output / power input.

• % COP (COP 100) is the heat generator efficiency.

Commissioning When, after all or part of a fixed building service or on-site electricity generation system has been installed, replaced or altered, the system is taken from a state of static completion to working order. Testing and adjusting are carried out for fixed building services, as necessary, to ensure that the whole system uses no more fuel and power than is reasonable in the circumstances. Testing and adjusting are carried out for on-site electricity
generation systems, as necessary, to ensure that the whole system produces the maximum amount of electricity that is reasonable in the circumstances.

For each system, commissioning includes all of the following.

• Setting to work.

• Regulation (that is, testing and adjusting repetitively) to achieve the specified performance.

• Calibration.

• Setting up and testing the associated automatic control systems.

• Recording the system settings and the performance test results that have been accepted as satisfactory.

Community heating system A system that supplies heat from a central source to more than one dwelling or premises within a single building.

Consequential improvements Those energy efficiency improvements required by regulation 28.

**Controlled service or fitting* Defined in regulation 2(1) as a service or fitting in relation to which Part G [sanitation, hot water safety and water efficiency], H [drainage and waste disposal], J [combustion appliances and fuel storage systems], L [conservation of fuel and power] or P [electrical safety] of Schedule 1 imposes a requirement.

Cooling load The rate at which heat is removed from the space to maintain a desired air temperature.

District heat networks Supply heat from a central source to consumers, via a network of underground pipes carrying hot water. Heat networks can cover a large area or even an entire city, or can be relatively local, supplying a small cluster of buildings.

Dwelling A self-contained unit designed to accommodate a single household.

NOTE: Buildings exclusively containing rooms for residential purposes, such as nursing homes, student accommodation and similar, are not dwellings. In such cases, Approved Document L, Volume 2: Buildings other than dwellings applies.

Dwelling emission rate The dwelling CO2 emission rate expressed as kgCO2/(m2·year) and determined using the Standard Assessment Procedure.

Dwelling fabric energy efficiency rate Expressed as kWh/(m2·year) and determined using the Standard Assessment Procedure.

Dwelling primary energy rate Expressed as kWhPE/(m2·year) and determined using the Standard Assessment Procedure.

Economically feasible The capital cost of a measure will be recouped in energy savings within a reasonable time. For the purposes of this document, economically feasible means that the measure would achieve a simple payback after one of the following.

• 7 years, for the installation of thermostatic room controls.

• 15 years, for any other measure.

Emergency escape lighting The emergency lighting that illuminates an area for the safety of people leaving that area or for people attempting to stop a dangerous process before leaving that area.

**Energy efficiency requirements*Defined in regulation 2(1) as the requirements of regulations 23, 25A, 25B, 26, 26A, 26C, 28, 40 and 43 and Part L of Schedule 1.

Energy performance certificateDefined in the Energy Performance of Buildings (England and Wales) Regulations 2012 as a certificate which:

a. in the case of a certificate entered on the register before 9th January 2013 complied with the requirements of regulation 11(1) of the Energy Performance of Buildings (Certificates and Inspections) (England and Wales)
Regulations 2007;

b. in the case of a certificate entered on the register on or after 9th January 2013 complies with the requirements of regulation 9(1) of these Regulations; or

c. complies with the requirements of regulation 29 of the Building Regulations 2010.

Envelope area (the measured part of the building) The total area of all floors, walls and ceilings bordering the internal volume that is the subject of a pressure test. This includes walls and floors below external ground level. Overall internal dimensions are used to calculate this envelope area, and no subtractions are made for the area of the junctions of internal walls, floors and ceilings with exterior walls, floors and ceilings.

Existing district heat network A district heat network that is either in operation or is under construction on 15 June 2022. For these purposes, under construction means any of the following.

• The building to house the energy centre has been constructed.

• There is a heat offtake agreement signed between the heat network and a third party.

• Excavation for pipework has been completed.

**Fixed building services* Defined in regulation 2(1) as any part of, or any controls associated with:

a. fixed internal or external lighting systems (but not including emergency escape lighting or specialist process lighting);

b. fixed systems for heating, hot water, air conditioning or mechanical ventilation; or

c. any combination of systems of the kinds referred to in paragraph (a) or (b).

Fixed external lighting Lighting fixed to an external surface of the building and supplied from the occupier’s electrical system. It excludes lighting in common areas of blocks of flats and in other communal accessways.

Hard water Water which has a high mineral content. For the purposes of this approved document, hard water is water that has a total water hardness of greater than 200ppm of CaCO3.

Heating appliance or heat generator The part of a heating system that generates useful heat using one or more of the following processes.

• The combustion of fuels in, for example, a boiler.

• The Joule effect, taking place in the heating elements of an electric resistance heating system.

• Capturing heat from ambient air, ventilation exhaust air, or a water or ground heat source using a heat pump.

Heating plant emission rate The annual CO2 emissions from the fuel and power consumed by the heating plant to deliver space heating and hot water, offset by the emissions saved as a result of any electricity generated by the heating plant, divided by the heat output over a year. Measured in kilograms of CO2.

Heating zone A conditioned area of a building which is on a single floor and has the same thermal characteristics and temperature control requirements throughout.

Intermediate floor A floor in a building above the ground floor.

Light fitting A fixed light or a lighting unit, and can comprise one or more lamps and lamp holders, control gear and an appropriate housing. The control gear may be integrated in the lamp or located elsewhere, in or near the fixed light.
Light source lumens The sum of the average initial (100 hour) lumen output of all light sources in a luminaire.

Load compensation A control function that maintains internal temperature by varying the flow temperature from the heat generator relative to the measured response of the heating system.

**Major renovation* Defined in regulation 35 as the renovation of a building where more than 25% of the surface area of the building envelope undergoes renovation.

**Material change of use* Defined in regulation 5 as: Where there is a change in the purposes for which or the circumstances in which a building is used, so that after that change:

a. the building is used as a dwelling, where previously it was not;

b. the building contains a flat, where previously it did not;

c. the building is used as an hotel or a boarding house, where previously it was not;

d. the building is used as an institution, where previously it was not;

e. the building is used as a public building, where previously it was not;

f. the building is not a building described in classes 1 to 6 in Schedule 2, where previously it was;

g. the building, which contains at least one dwelling, contains a greater or lesser number of dwellings than it did previously;

h. the building contains a room for residential purposes, where previously it did not;

i. the building, which contains at least one room for residential purposes, contains a greater or lesser number of such rooms than it did previously;

j. the building is used as a shop, where it previously was not; or

k. the building is a building described in regulation 7(4)(a), where previously it was not.

Primary circulation An assembly of water fittings in which water circulates between a heat source and a primary heat exchanger inside a hot water storage vessel, including any space heating system.

Primary energy Energy, from renewable and nonrenewable sources, that has not undergone any conversion or transformation process.

Renewable technology Technology that uses renewable resources, which are naturally replenished on a human timescale, to produce electricity. Resources include wind, wave, marine, hydro, biomass and solar.

Rooflight A glazed unit installed out of plane with the surface of the roof on a kerb or upstand. Also sometimes referred to as a skylight.

Roof window A window installed in the same orientation as, and in plane with, the surrounding roof.

**Room for residential purposes* Defined in regulation 2(1) as a room, or a suite of rooms, which is not a dwelling-house or a flat and which is used by one or more persons to live and sleep and includes a room in a hostel, an hotel, a
boarding house, a hall of residence or a residential home, but does not include a room in a hospital, or other similar establishment, used for patient accommodation.

Seasonal coefficient of performance (SCOP) A measure of the efficiency of a heat pump over the designated heating season, measured using the procedures in BS EN 14825.

Seasonal energy efficiency ratio (SEER) The total amount of cooling energy provided by a single cooling unit over a year, divided by the total energy input to that single cooling unit over the same year.

Secondary circulation An assembly of water fittings in which water circulates in supply pipes or distributing pipes of hot water storage systems.

Secondary heating A space heating appliance or system which operates separately from the main heating system in the dwelling and does not provide most of the heating in the dwelling – for example, a decorative fuel-effect fire in a room which also contains radiators for a central heating system.

SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) The methodology for determining boiler efficiency defined in the Standard Assessment Procedure, Appendix D.

Simple payback The amount of time it will take to recover the initial investment through energy savings, calculated by dividing the marginal additional cost of implementing an energy efficiency measure by the value of the annual energy savings achieved by that measure, taking no account of VAT. The following guidance should be used.

• The marginal additional cost is the additional cost (materials and labour) of incorporating, for example, additional insulation – not the whole cost of the work.

• The cost of implementing the measure should be based on prices current at the date when the application is made to the building control body and be confirmed in a report signed by a suitably qualified person.

• The annual energy savings should be estimated using the Standard Assessment Procedure.

• The energy prices that are current when the application is made to the building control body should be used when evaluating energy savings.

Current prices are given on the BEIS website, at:https://www.gov.uk/government/collections/ quarterly-energy-prices.
Space cooling system A system for cooling the temperature of the air in a space.

Specialist process lighting Lighting to illuminate specialist tasks within a space rather than the space itself. Specialist process lighting includes theatre spotlights, projection equipment, lighting in TV and photographic studios, medical lighting in operating theatres and doctors’ and dentists’ surgeries, illuminated signs, coloured or stroboscopic lighting, and art objects with integral lighting, such as sculptures, decorative fountains and chandeliers.

Standard Assessment Procedure The current approved procedure for assessing the performance of dwellings in line with this document (Approved Document L, Volume 1). The Standard Assessment Procedure is detailed in The Government’s Standard Assessment Procedure for Energy Rating of Dwellings version 10.

Target emission rate The maximum CO2 emission rate for the dwelling, expressed as kgCO2/(m2·year) and determined using the Standard Assessment Procedure.

Target fabric energy efficiency rate The minimum dwelling fabric energy efficiency, expressed as kWh/(m2·year) and determined using the Standard Assessment Procedure.

Target primary energy rate The maximum primary energy use for the dwelling in a year, expressed as kWhPE/(m2·year) and determined using the Standard Assessment Procedure.

Thermal bridging Occurs when part of a thermal element has significantly higher heat transfer than the materials surrounding it.

**Thermal element* Defined in regulation 2(3) and 2(4) as follows.

2(3) In these Regulations “thermal element” means a wall, floor or roof (but does not include windows, doors, roof windows or roof-lights) which separates a thermally conditioned part of the building (“the conditioned space”) from

a. the external environment (including the ground); or

b. in the case of floors and walls, another part of the building which is

i. unconditioned;

ii. an extension falling within class 7 of Schedule 2; or

iii. where this paragraph applies, conditioned to a different temperature, and includes all parts of the element between the surface bounding the conditioned space and the external environment or other part of the building as the case may be.

2(4) Paragraph 2(3)(b)(iii) only applies to a building which is not a dwelling, where the other part of the building is used for a purpose which is not similar or identical to the purpose for which the conditioned space is used.

Thermal envelope The combination of thermal elements of a building that enclose a particular conditioned indoor space or group of indoor spaces.

Thermal separationOccurs where a dwelling and a conservatory or porch are divided by walls, floors, windows and doors to which one of the following applies.

• The U-values are similar to, or in the case of a newly constructed conservatory or porch not exceeding, the U-values of the corresponding exposed elements elsewhere in the dwelling.

• In the case of a newly constructed conservatory or porch, windows and doors have similar draught-proofing provisions as the exposed windows and doors elsewhere in the dwelling.

Total useful floor areaThe total area of all enclosed spaces, measured to the internal face of the external walls. When calculating total useful floor area, both of the following should be takeninto account.

• The area of sloping surfaces such as staircases, galleries, raked auditoria and tiered terraces should be taken as their area on plan.

• Areas that are not enclosed, such as open floors, covered ways and balconies, should be excluded.

NOTE: This area is the gross internal floor area as measured in accordance with the Code of Measuring Practice by the Royal Institution of Chartered Surveyors (RICS).

U-value A measure of the ability of a building element or component to conduct heat from a warmer environment to a cooler environment. It is expressed as the quantity of heat (in watts) that will flow through 1m2 of area divided by the difference in temperature (in degrees K) between the internal and external environment. The unit is W/(m2·K).
Weather compensation A system which enables the operating flow temperature of a heating system to be varied. An external sensor communicates with one inside the boiler. The temperature is varied by either of the following.

• Modulating the heat generator output (direct acting).

• Using a mixing valve to adjust the flow temperature to the heat emitters.

Wet heating system When a heating appliance (usually a boiler) produces hot water which is distributed around the dwelling to heat emitters.

Appendix B: Reporting evidence of compliance

BREL report

B1 The Buildings Regulations England Part L (BREL) report and photographic evidence should be provided to the building control body and to the building owner to show that building work complies with energy efficiency requirements.

B2 SAP 10 will produce the BREL report for the building as a standard output option.

B3 Two versions of the BREL report should be produced, using the approved software.

a. The first, the design stage BREL report, before works begin, to include all of the following.

i. The target primary energy rate and dwelling primary energy rate.

ii. The target emission rate and dwelling emission rate.

iii. The target fabric energy efficiency rate and dwelling fabric energy efficiency rate.

iv. A supporting list of specifications.

b. The second, the as-built BREL report, to include all of the following.

i. The target primary energy rate and as-built dwelling primary energy rate.

ii. The target emission rate and as-built dwelling emission rate.

iii. The target fabric energy efficiency rate and as-built dwelling fabric energy efficiency rate.

iv. A supporting list of specifications and any changes to the list of specifications that was provided at design stage.

The building control body can then use these reports to help check that what was designed has been built. The software includes a facility to compare the design stage and as-built data input files and automatically produce a schedule of changes.

B4 The as-built BREL report should be signed by the person carrying out the SAP assessment to confirm that the as-built calculations are accurate and that the supporting documentary evidence and photographs have been reviewed (see paragraphs B6 and B7).

B5 The as-built BREL report should be signed by the developer to confirm that the dwelling has been constructed or completed according to the specifications in the report.

Photographic evidence

B6 Photographs should be taken for each dwelling on a development as a record during the construction of a property. The photographs should be made available to the energy assessor and the building control body. Anyone may take the photographs.

B7 Photographs should be taken of typical details as listed below and should be unique to each property. One photograph per detail should be recorded. Additional images, such as a closeup detail, should be provided only when necessary (see below). Photographs should be taken at appropriate construction stages for each detail when completed, but prior to closing-up works.

Foundations/substructure and ground floor, to show thermal continuity and quality of insulation in the following places.

a. At ground floor perimeter edge insulation.

b. At external door threshold.

c. Below damp-proof course on external walls.

External walls: for each main wall type, to show thermal continuity and quality of insulation for the following.

a. Ground floor to wall junction.

b. Structural penetrating elements.

NOTE: For blown fill, photos should show clean cavities and clean brick ties with very limited mortar droppings.

Roof: for each main roof type, to show thermal continuity and quality of insulation at the following.

a. Joist/rafter level.

b. Eaves and gable edges.

Openings: for each opening type (one image per wall or roof type is sufficient), to show thermal continuity and quality of insulation with photographs of the following.

a. Window positioning in relation to cavity closer or insulation line.

b. External doorset positioning in relation to cavity closer or insulation line

Airtightness: additional photographs for all details 1–4 to show airtightness details (only if not included or visible in continuity of insulation image).
Building services: for all plant associated with space heating, hot water, ventilation and low or zero carbon technology equipment within or on the building, show the following.

a. Plant/equipment identification label(s), including make/model and serial number.

b. Primary pipework continuity of insulation.

c. Mechanical ventilation ductwork continuity of insulation (for duct sections outside the thermal envelope).

B8 Photographs should be digital and of sufficient quality and high enough resolution to allow a qualitative audit of the subject detail. Close-up photographs may be needed where a long shot image provides insufficient detail. More than one image of each detail may be needed. Geolocation should be enabled to confirm the location, date and time of each image. Each image file name should include a plot number and detail reference according to the numbers used in paragraph B7. For example, Plot 1 eaves detail would be P1/3b.

Appendix C: Work to thermal elements

C1 This appendix provides guidance on the cost-effectiveness of insulation measures during various types of work on a thermal element. Table C1 sets out target U-values that would be considered to represent reasonable improvements in ordinary cases and examples of construction that may be used to achieve the proposed performance.

C2 If it is not reasonable to meet the target U-values in Table C1, considering technical risk and practicality of the work in relation to the dwelling and impacts on adjoining buildings, then the U-value should be as close to the target value as practically possible.

C3 The final column in Table C1 provides guidance on specific issues that may need to be considered to determine an appropriate course of action. In general, the proposed works should take account of all of the following.

a. The requirements of any other relevant parts of Schedule 1 to the Building Regulations.

b. The general guidance on technical risk relating to insulation improvements contained in the Building Research Establishment’s BR 262.

c. For buildings falling within the categories set out in paragraphs 0.8 to 0.13, Historic England’s Energy Efficiency and Historic Buildings: Application of Part L of the Building Regulations to

Historic and Traditionally Constructed Buildings.

C4 General guidance is available from relevant British Standards.

general G6
Table C1 Cost-effective U-value targets when undertaking renovation works to thermal elements

general G6
Table C1 Continued

general G6
Table C1 Continued

general G6
Table C1 Continued

Appendix D: Specification for a home built with a heat pump

D1 This appendix provides a good practice specification for a dwelling built with a heat pump.

D2 By using this specification, the dwelling should pass the target primary energy rate and target emission rate. However, this should be checked through energy calculations.

general G6
Table D1 Summary of notional dwelling specification for new dwellings

general G6
Table D1 Continued

Appendix E: Standards referred to

BS 1566-1 Copper indirect cylinders for domestic purposes. Open vented copper cylinders. Requirements and test methods [2002 + A1: 2011]

BS 3198 Specification for copper hot water storage combination units for domestic purposes [1981]

BS 5250 Management of moisture in buildings. Code of practice [2021]

BS 5422 Method for specifying thermal insulating materials for pipes, tanks, vessels, ductwork and equipment operating within the temperature range -40°C to +700°C [2009]

BS 5864 Installation and maintenance of gasfired ducted air heaters of rated heat input not exceeding 70 kW net (2nd and 3rd family gases). Specification [2019]

BS 6229 Flat roofs with continuously supported flexible waterproof coverings. Code of practice [2018]

BS 7593 Code of practice for the preparation, commissioning and maintenance of domestic central heating and cooling water systems [2019]

BS 7977 Specification for safety and rational use of energy of domestic gas appliances

BS 7977-1 Radiant/convectors [2009 + A1: 2013]

BS 7977-2 Combined appliances. Gas fire/back boiler [2003]

BS 8213-4 Windows and doors. Code of practice for the survey and installation of windows and external doorsets [2016]

BS EN 253 District heating pipes. Bonded single pipe systems for directly buried hot water networks. Factory made pipe assembly of steel service pipe, polyurethane thermal insulation and a casing of polyethylene [2019]

BS EN 449 Specification for dedicated liquefied petroleum gas appliances. Domestic flueless space heaters (including diffusive catalytic combustion heaters) [2002 + A1: 2007]

BS EN 509 Decorative fuel-effect gas appliances [2000]

BS EN 613 Independent gas-fired convection heaters [2001]

BS EN 805 Water supply. Requirements for systems and components outside buildings [2000]

BS EN 1264-4 Water based surface embedded heating and cooling systems. Installation [2021]

BS EN 1266 Independent gas-fired convection heaters incorporating a fan to assist transportation of combustion air and/or flue gases [2002]

BS EN 12831-3 Energy performance of buildings. Method for calculation of the design heat load. Domestic hot water systems heat load and characterisation of needs [2017]

BS EN 12897 Water supply. Specification for indirectly heated unvented (closed) storage water heaters [2016 + A1: 2020]

BS EN 12975-1 Thermal solar systems and components. Solar collectors – General requirements [2006 + A1: 2010]

BS EN 13278 Open fronted gas-fired independent space heaters [2013]

BS EN 14511-2 Air conditioners, liquid chilling packages and heat pumps for space heating and cooling and process chillers, with electrically driven compressors. Test conditions [2018]

BS EN 14825 Air conditioners, liquid chilling packages and heat pumps, with electrically driven compressors, for space heating and cooling. Testing and rating at part load conditions and calculation of seasonal performance [2018]

BS EN 14829 Independent gas-fired flueless space heaters for nominal heat input not exceeding 6 kW [2007]

BS EN 15502-2-1 Gas-fired central heating boilers. Specific standard for type C appliances and type B2, B3 and B5 appliances of a nominal heat input not exceeding 1 000 kW [2012 + A1: 2016]

BS EN 15502-2-2 Gas-fired central heating boilers. Specific standard for type B1 appliances [2014]

BS EN 17082 Domestic and non-domestic gas-fired forced convection air heaters for space heating not exceeding a net heat input of 300 kW [2019]

BS EN ISO 9806 Solar energy. Solar thermal collectors. Test methods [2017]

BS EN ISO 12567 Thermal performance of windows and doors. Determination of thermal transmittance by the hot-box method

BS EN ISO 12567-1 Complete windows and doors [2010]

BS EN ISO 12567-2 Roof windows and other projecting windows [2005]

BS EN ISO 13370 Thermal performance of buildings. Heat transfer via the ground. Calculation methods [2007 incorporating corrigendum March 2009]

BS EN ISO 13788 Hygrothermal performance of building components and building elements. Internal surface temperature to avoid critical surface humidity and interstitial condensation. Calculation methods [2012]

BSI PAS 67 Laboratory tests to determine the heating and electrical performance of heat-led micro-cogeneration packages primarily intended for heating dwellings [2013]

Appendix F: Documents referred to

Legislation

Ancient Monuments and Archaeological Areas Act 1979, c. 46

Building (Approved Inspectors etc.) Regulations 2010, SI 2010/2215

Building Regulations 2010, SI 2010/2214 Ecodesign Commission Regulation No. 2016/2281

Ecodesign for Energy-Related Products Regulations 2010, SI 2010/2617

Energy-Related Products Directive 2009/125/EC Planning (Listed Buildings and Conservation Areas) Act 1990, c. 9

Documents

Building Research Establishment (BRE)

(www.bre.co.uk)

BR 262 Thermal Insulation: Avoiding Risks. Third Edition [2002]

BR 443 Conventions for U-value Calculations [2019]

BR 497 Conventions for Calculating Linear Thermal Transmittance and Temperature Factors. Second Edition [2016]

Information Paper 1/06 Assessing the Effects of Thermal Bridging at Junctions and around Openings in the External Elements of Buildings [2006]

FB 59 Design of Low-temperature Domestic Heating Systems: A Guide for System Designers and Installers [2013]

Chartered Institute of Plumbing and Heating Engineering (CIPHE)

(www.ciphe.org)

Plumbing Engineering Services Design Guide [2002]

Chartered Institution of Building Services Engineers (CIBSE)

(www.cibse.org)

Guide A Environmental Design [2015]

TM23 Testing Buildings for Air Leakage [2000]

Department for Business, Energy and Industrial Strategy (BEIS)

(www.gov.uk/beis)

The Government’s Standard Assessment Procedure for Energy Rating of Dwellings, SAP 10. Available at www.bregroup.com/sap/sap10/

Department for Environment, Food and Rural Affairs (DEFRA)

Method to Evaluate the Annual Energy

Performance of Micro-cogeneration Heating Systems in Dwellings [2008]

Glass and Glazing Federation (GGF)

(ggf.org.uk)

Glazing Manual Data Sheet 2.3, Guide to the Calculation of Energy Ratings for Windows, Roof Windows and Doors [2016]

HETAS

(www.hetas.co.uk)

The HETAS Guide to Approved Solid Fuel, Wood and Biomass Products and Services. List no. 26 [2020]

Historic England

(historicengland.org.uk)

Energy Efficiency and Historic Buildings: Application of Part L of the Building Regulations to Historic and

Traditionally Constructed Buildings [2017]

Hot Water Association

(www.hotwater.org.uk)

Performance Specification for Thermal Stores [2010]

Local Authority Building Control

(www.labc.co.uk)

Construction Details, available at: www.labc.co.uk/ business/construction-details

Ministry of Housing, Communities and Local Government (MHCLG)

Manual to the Building Regulations: A Code of Practice for Use in England [2020]

Office of the Deputy Prime Minister (ODPM)

Guide to the Condensing Boiler Installation Assessment Procedure for Dwellings [2005]

National Association of Rooflight Manufacturers (NARM)

(www.narm.org.uk)

Technical Document NTD02 Assessment of Thermal Performance of Out-of-plane Rooflights [2010]

Appendix A~F