Domestic Building Services Compliance Guide for Scotland

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Building Standards Division

Domestic

Building Services

Compliance Guide

For Scotland

2015 Edition

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Note:

This document applies to Scotland only. For other jurisdictions in the UK, it will be necessary to consult their own building regulations and guidance.

Any reference to the Building regulations in this guide is to the Building (Scotland) Regulations 2004 (as amended).

This guidance comes into effect on 1 October 2015 and is applicable to:

• work that is subject to a building warrant submitted on or after 1 October 2015; or

• work which, by virtue of regulation 5 of and Schedule 3 to the Building (Scotland) Regulations 2004, does not require a building warrant, other than work that is:

•o completed before 1st October 2015; or

•o not completed before that date where the contract for the work is entered into before 1 October 2015 and the work is completed before 31st January 2016.

Whilst publication of this guide is intended to support standardisation of the specification and expected performance of fixed building services throughout the UK, please note that guidance in section 1.8 on replacement of primary heating appliances differs in Scotland from that applied within building regulations elsewhere in the UK.

Produced by the Buildings Standards Division

First published: October 2014

Version 1.0

Document Version Control

Title: Domestic Building Standards Compliance Guide for Scotland – 2015 Edition

Purpose: To provide guidance on compliance with building regulations, namely standards 6.3 to 6.7, as set out in section 6 (energy) of the 2015 Domestic Technical Handbook. This guidance is applicable as described in the note provided above.

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1.1Scope

This guide provides detailed guidance for the installation of fixed building services in new and existing non-domestic buildings in support of compliance with the energy efficiency requirements set out under standards 6.3 to 6.7 of the building regulations.

This edition covers the design, installation and commissioning of:

• conventional means of providing primary and secondary space heating, domestic hot water, mechanical ventilation, comfort cooling and internal & external lighting; and

• low carbon generation of heat by heat pumps, solar thermal panels, and micro- combined heat and power systems.

The guide sets out recommended minimum energy efficiency standards for components of building services systems, including the use of controls. For systems installed in new dwellings, the standards are minimum design limits (or back-stop values). For new or replacement systems and components installed in existing dwellings, the standards represent appropriate provision for complying with building regulations.

It is important to note that standards higher than many of these recommended minimum standards will need to be achieved if:

• new dwellings are to meet the target carbon dioxide emission rate (TER) calculated under standard 6.1 using SAP1

• systems are to comply with the Microgeneration Certification Scheme standards2 that enable building owners to receive payments under the Renewable Heat Incentive (RHI) and qualify for Green Deal funding

• products are to be recognised as renewable technologies under the Renewable Energy Directive.

The guide includes some supplementary information that identifies good practice design and installation standards that exceed the minimum standards in this guide. Microgeneration Certification Scheme standards are an example of good practice standards.

A summary of recommended minimum energy efficiency standards is presented in Table 1 at the end of this section.

1.2Innovative systems

It is also important to note that this guide covers a range of frequently occurring situations and deals with the most commonly used fixed building services technologies. In doing so it neither endorses these methods and technologies nor excludes other more innovative technologies that may offer an alternative means of meeting the functional requirements of building regulations.

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Where the alternative technology has been the subject of a recognised testing procedure that assesses its energy performance, this may be used to indicate that the system is adequately efficient. In the event that there is no recognised testing standard, suitable calculations or modelling methods should be used to show the carbon performance of the system.

1.3European Directives

The design and installation of fixed building services products, such as boilers, circulators and heat pumps, shall at the appropriate time comply with all relevant requirements of EU Directives as implemented in the United Kingdom. There are a number of Directives with requirements that directly or indirectly control the energy efficiency of building services.

The Ecodesign Directive 2009/125/EC provides a framework for establishing requirements for ‘energy-related’ products placed on the EU market. Current requirements cover ‘energy- using’ products such as boilers, light bulbs and washing machines. In the future, requirements will also cover products such as windows, insulation material and shower heads whose use has an impact on energy consumption.

The requirements are set out in Commission Regulations listed in the document http://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf. Products covered by the regulations can only be CE-marked and placed on the market if they meet the ecodesign standards specified.

At the time of preparation of this guide, Commission Regulations existed or were being developed for:

• space heaters and combination heaters

• water heaters and hot water storage tanks

• glandless standalone circulators and glandless circulators integrated in products

• water pumps

• air conditioners and comfort fans

• fans driven by motors with an electric input power between 125W and 500W

• lighting products in the domestic and tertiary sectors

• electric motors.

The intention is that the recommended minimum product standards in this guide should at least match the energy efficiency standards set out in Commission Regulations as they come into force. For example, although the implementing regulations for hot water storage tanks were published in September 2013, the standards do not come into force until September 2017. If in any doubt as to whether a product is subject to minimum ecodesign standards, check the Commission document above.

The Energy Labelling Directive 2010/30/EU compliments the Ecodesign Directive by providing a framework for labelling of energy-related products including lamps, luminaires, household air conditioners and washing machines. The Energy Label classifies products on an A to G scale, ‘pulling’ the market towards more efficient products by better informing consumers. The Ecodesign Directive, by contrast, uses regulation to ‘push’ the market away from the worst performing products.

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The Renewable Energy Directive 2009/28/EC provides a framework for the promotion of energy from renewable resources. It sets a mandatory UK target of 15% energy generation from renewable sources by 2020 – the ‘renewable energy obligation’ – as a contribution to meeting the EU’s overall target of 20%. Of relevance to building services is that the Directive identifies criteria for training and certification of installers of renewables. The Directive also specifies in Annex VII the standards that heat pumps must achieve to be recognised as renewable technologies by the Directive.

The Energy Efficiency Directive 2012/27/EU establishes a common framework of measures for the promotion of energy efficiency within the EU in order to ensure that the EU meets its target of a 20% reduction in primary energy consumption by 2020. Legislation to implement the Directive in the UK will be published by 5 June 2014. Included will be requirements for public authorities to purchase only energy-efficient products, services and buildings; and requirements for heat meters to be fitted in apartments and buildings connected to a central source of heating or a district heating network. For more information on the specific requirements and technical standards, see the DECC website3.

The Energy Performance of Buildings Directive 2010/31/EU is a recast of the original 2002/91/EC Directive, which in 2002 introduced requirements for:

• the establishment of a methodology for calculating the integrated energy performance of buildings

• minimum energy performance requirements for new buildings, and, where feasible, for larger buildings undergoing major renovation

• energy performance certification of buildings, and

• inspections of heating and air conditioning systems.

The recast Directive included a new requirement to consider in the design of new buildings the feasibility of using renewables and other ‘high-efficiency alternative systems’. There is no mandatory format for this assessment, but it is necessary to declare, as part of the building warrant application, how this has been carried out4.

The building regulations already meet specific requirements of the Directive (for example by setting standards for new buildings and new building work). For guidance on the most recent changes affecting new and existing domestic buildings, see Section 6 Energy of the Non- Domestic Technical Handbook5. For guidance on other requirements relating to building certification and inspection of heating and air conditioning systems, see the BSD website6.

1.4Status of guide

The building regulations in Scotland are expressed in terms of functional standards. These standards are statements of functions the complete building must fulfil or allow. The standards are set out in building regulations and are intended to

• secure the health, safety and welfare and convenience of persons in or about buildings;

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• further the conservation of fuel and power; and

• further the achievement of sustainable development.

These functional requirements are often drafted in broad terms and so, from the standard alone, it may not always be immediately clear to a person carrying out work how to comply with the relevant requirements. Consequently, the Building Standards Division issues guidance in the form of Technical Handbooks and other published information, such as this document, which provide practical guidance on ways of complying with specific aspects of the building regulations in most common building situations.

The Technical Handbooks are intended to provide practical guidance, but they are not intended to be comprehensive. Consequently, they may contain references to other documents which will provide more detailed information and assistance on parts of the guidance. This guide is one of those documents. It provides more detailed information on the guidance contained in Section 6 Energy of the Domestic Technical Handbook about compliance with the energy efficiency requirements which apply when installing fixed building services in new and existing buildings.

If you follow the guidance in the Technical Handbooks and companion documents, such guidance may be relied on in any proceedings as tending to negative liability for an alleged contravention of the building regulations (refer to section 0 of the Technical Handbooks for further explanation)

However, in each every case it is for the verifier (local authority) to determine whether work complies with the requirements of the building regulations. Where there is doubt, it is appropriate to check with the verifier before starting work to establish what is necessary for compliance with building regulations. In Scotland, all new buildings and much work to existing buildings will require the issue of a building warrant prior to any works commencing on site. Information on works which must comply with building regulations but for which a building warrant is not required are set out in schedule 3 to regulation 5 (refer to section 0 of the Technical Handbooks).

1.5How to use this guide

The guide is fdivided into the following sections:

Section 1: Introduction and summary of energy efficiency standards

• Fuel-based

Section 2: Gas-fired space and water heating

Section 3: Oil-fired space and water heating

Section 4: Electric heating

Section 5: Solid fuel heating

• Technology-specific

Section 6: Community heating

Section 7: Underfloor heating

Section 8: Mechanical ventilation

Section 9: Heat pumps

Section 10: Comfort cooling

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Section 11: Solar water heating

Section 12: Lighting

Section 13: Micro-combined heat and power

Section 14: Heating system circulators

For any particular application, reference may need to be made to more than one section.

Supplementary information is shown against a blue background. This may be further information to help in establishing the minimum energy efficiency provisions needed to comply with the building regulations or it may be guidance on best practice that goes beyond the recommended minimum standards.

Key terms are printed in italics and are defined at appropriate points throughout the guide.

1.6Key terms

Fixed building services means any part of, or any controls associated with:

a.fixed internal or external lighting systems, but does not include emergency escape lighting or specialist process lighting

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

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

New system means a fixed building services system installed:

a.in a new building

b.for the first time in an existing building

c.as a complete replacement for a system in an existing building.

Seasonal efficiency means the efficiency value used by SAP for a heating appliance. For gas, LPG and oil boilers that have been tested for efficiency, this is SEDBUK7.

1.7Work on existing systems

A requirement of building regulations is that work on existing buildings should be carried out in such a way that when the work is complete:

a.the work itself complies with the applicable requirements of building regulations

b.the parts of the building not affected by the work are no worse in relation to the requirements of regulations than before the work was started.

This means that when a system component like a boiler or a room thermostat is replaced, only the new component is expected to comply with the provisions in this guide (which in some cases may be lower than for new systems).

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It is not a general requirement to upgrade the rest of the existing system, but this guide does include some recommendations on minor upgrades for compliance with building regulations where they would be cost-effective and may be necessary to ensure efficient operation of the new component.

Some of the supplementary information is guidance on good practice that, while not essential for compliance with building regulations, would help to save energy. For example, it is convenient and timely to fit thermostatic radiator valves when replacing a boiler and the system has been drained down.

1.8Replacement of primary heating appliances

When replacing an existing appliance, the seasonal efficiency of the new equipment should be as stated in the relevant fuel-based section of this guide, subject to any guidance identifying alternatives in exceptional circumstances.

1.9Summary of recommended minimum energy efficiency standards

Table 1 summarises the recommended minimum energy efficiency standards for buiding services in domestic buildings.

Table 1: Recommended minimum energy efficiency standards for building services8

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Table 1: Recommended minimum energy efficiency standards for building services8

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Table 1: Recommended minimum energy efficiency standards for building services8

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Table 1: Recommended minimum energy efficiency standards for building services8

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2.1Scope of guidance

This section provides guidance on the specification of gas-fired space heating and hot water systems14 in dwellings to meet relevant energy efficiency requirements in building regulations. The guidance applies to systems fuelled by natural gas and liquid petroleum gas (LPG) and covers:

• wet central heating systems

• range cookers with integral central heating boilers

• warm air heating systems

• fixed independent space heating devices.

2.2Gas-fired wet central heating systems

New systems

New systems for gas-fired wet central heating in new and existing dwellings should meet the minimum standards for:

a.boiler efficiency, system circulation, hot water storage, system preparation and commissioning in Table 2

b.boiler interlock, zoning, and time and temperature control of the heating and hot water circuits in Table 3

c.pipework insulation in Table 5.

Existing systems

Components installed as replacements in existing systems should meet the same standards as for new systems, except where indicated otherwise in Table 4.

Table 4 in addition identifies good practice upgrades to the rest of the system (beyond the requirements of building regulations) when making planned and emergency replacements.

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Table 2: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for gas-fired wet central heating systems

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Table 2: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for gas-fired wet central heating systems

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Table 2: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for gas-fired wet central heating systems

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Table 3: Recommended minimum standards for control of gas-fired wet central heating systems 1

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Table 4: Recommended minimum standards when replacing components of gas-fired wet central heating systems 1

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Table 5: Recommended minimum standards for insulation of pipework in gas-fired wet central heating systems

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2.3Gas-fired range cookers with integral central heating boiler

Note: This section does not apply to appliances with fully independent boiler and cooker parts within a shared case. For these, the standards for the boiler are as set out in Section 2.2.

Where gas-fired range cookers with an integral central heating boiler (within a single appliance body), are provided as part of a new system or as a replacement component:

a.The appliance should have two independently controlled burners (one for the cooking function and one for the boiler).

b.The SEDBUK 2009 efficiency of the integral boiler should be not less than 75%. The manufacturer’s declaration of appliance performance and SEDBUK value should include the following statement and information:

i. Seasonal efficiency (SEDBUK) = xx % ii. Case heat emission value = yy kW iii. Heat transfer to water at full load = zz kW iv. The values are used in the UK Government’s Standard Assessment Procedure (SAP) for the energy rating of dwellings. The test data from which the values have been calculated has been certified by [insert name and/or identification of Notified body]. See: www.rangeefficiency.org.uk.

If the integral boiler is a condensing boiler, the declaration should make clear whether the efficiency has been calculated in accordance with SEDBUK 2005 or SEDBUK 2009. If it does not, then SEDBUK 2005 must be assumed.

c.The integral boiler should meet the minimum standards for system circulation, hot water storage, system preparation, commissioning, controls and insulation in Tables 2, 3 and 5 (gas-fired central heating systems).

2.4Gas-fired warm air heating

New systems and replacement components for gas-fired warm air heating should meet the minimum standards for:

a.efficiency and installation in Table 6

b.zoning, time control and temperature control for (a) space heating without hot water and (b) space heating combined with water heating in Table 7.

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Table 6: Recommended minimum standards for efficiency and installation of gas-fired warm air heating systems

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Table 7: Recommended minimum standards for control of gas-fired warm air heating systems

2.5Gas-fired fixed independent space heating appliances

Fixed independent space heating appliances may be installed as a means of primary or secondary space heating.

Gas-fired fixed independent appliances for primary space heating

Where gas-fired fixed independent space heating appliances in new and existing dwellings are provided as the primary heat source:

a.The appliance should be one of the types described in Table 8.

b.The efficiency of the appliance (gross calorific value) should be not less than 63% (70% net).

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c.The appliance manufacturer’s declaration of appliance performance should include the following stratement and information:

The efficiency of this appliance has been measured as specified in [insert appropriate entry from Table 8] and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is xx %. The test data has been certified by [insert name and/or identification of Notified Body]. The gross efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.

d.In new dwellings, each appliance should be capable, either independently or in conjunction with room thermostats or other suitable temperature sensing devices, of controlling the temperatures independently in areas that have different heating needs (e.g. separate sleeping and living areas). In existing dwellings, wherever practical, temperature controls should be upgraded to the standards required for new dwellings.

Table 8: Appropriate types of natural gas and LPG-fired fixed independent appliances for primary space heating

British Standard designation (appliance type)

BS EN 1266:2002 – ‘Independent gas-fired convection heaters incorporating a fan to assist transportation of combustion air and/or flue gases’.

BS 7977-1:2009+A1:2013 – ‘Specification for safety and rational use of energy of domestic gas appliances. Radiant/convectors’.

BS EN 613:2001 – ‘Independent gas-fired convection heaters’.

BS EN 13278:2003 – ‘Open fronted gas-fired independent space heaters’.

Gas-fired fixed independent appliances for secondary space heating

Where gas-fired fixed independent space heating appliances are provided as the secondary heat source:

a.In new dwellings, the appliance efficiency (gross calorific value) should be not less than 63% (70% net).

b.In existing dwellings, the appliance efficiency (gross calorific value) should be not less than 45% (50% net).

c.The appliance manufacturer’s declaration of appliance performance should include the following statement and information:

The efficiency of this appliance has been measured as specified in [insert appropriate entry from Table 9] and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is xx%. The test data has been certified by [insert name and/or identification of Notified Body]. The efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.

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2.6Gas-fired fixed decorative fuel-effect fires

This type of appliance is intended for decorative purposes and therefore a minimum thermal efficiency is not specified. Note that for the purposes of SAP 2012 the efficiency of decorative fuel-effect fires is classed as 20% in the space heating requirement calculation. See Table 4a of SAP 2012.

Gas-fired decorative fires in new and existing dwellings should:

a.meet the product standards in BS EN 509: 2000 – ‘Decorative fuel-effect gas appliances’; and

b.number not more than one appliance per 100 m2 of dwelling floor area.

2.7Gas fires for secondary space heating provided as part of a combined fire and back boiler unit

Where gas fires are provided as a secondary heat source as part of a combined fire and back boiler unit in an existing system:

a.The appliance should be one of the types described in Table 10.

b.The efficiency (gross calorific value) of the appliance should be not less than the value in Table 10 for that type of appliance.

c.The appliance manufacturer’s declaration of appliance performance should include the following statement and information

The efficiency of this appliance has been measured as specified in [insert appropriate entry from Table 10] and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is xx%. The test data from which it has been calculated has been certified by [insert name and/or identification of Notified Body]. The efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.

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Table 10: Minimum appliance efficiencies for gas fires in a combined fire and back boiler unit

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Supplementary information

Energy Efficiency Best Practice in Housing:

CE30 Domestic heating by gas: boiler systems

CE51 Central heating system specifications (CHeSS)

CE54 Whole house boiler sizing method for houses and flats.

SBGI publications on gas boilers and gas fires: See www.sbgi.org.uk.

CORGI Domestic Manual Series:

GID1 Essential gas safety

GID2 Gas cookers and ranges

GID3 Gas fires and space heaters

GID5 Water heaters

GID7 Central heating wet and dry.

CORGI Design Guides:

WCH1 Wet central heating system design guide

WAH1 Warm air heating system design guide.

British and European Standards:

BS 5440-1:2008 – ‘Flueing and ventilation for gas appliances of rated input not exceeding 70 kW net (1st, 2nd and 3rd family gases). Specification for installation of gas appliances to chimneys and for maintenance of chimneys’.

BS 5440-2:2009 – ‘Flueing and ventilation for gas appliances of rated input not exceeding 70 kW net (1st, 2nd and 3rd family gases). Specification for the installation and maintenance of ventilation provision for gas appliances’.

BS EN 12828:2012 – ‘Heating systems in buildings. Design for water-based heating systems’.

BS EN 12831:2003 – ‘Heating systems in buildings. Method for calculation of the design heat load’.

BS EN 14336:2004 – ‘Heating systems in buildings. Installation and commissioning of water- based heating systems’.

BS 6798:2009 – ‘Specification for installation and maintenance of gas-fired boilers of rated input not exceeding 70 kW net’.

BS 5871-1:2007 – ‘Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Gas fires, convector heaters, fire/back boilers and heating stoves (2nd and 3rd family gases)’.

BS 5871-4:2007 – ‘Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Independent gas-fired flue less fires, convector heaters and heating stoves of nominal heat input not exceeding 6 kW (2nd and 3rd family gases)’.

BS 5871-2:2005 – ‘Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Inset live fuel effect gas fires of heat input not exceeding 15 kW, and fire/back boilers (2nd and 3rd family gases)’.

BS 5871-3:2005 – ‘Specification for the installation and maintenance of gas fires, convector heaters, fire/back boilers and decorative fuel effect gas appliances. Decorative fuel effect gas appliances of heat input not exceeding 20 kW (2nd and 3rd family gases)’.

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3.1Scope of guidance

This section provides guidance on the specification of oil-fired space heating and hot water systems15 in dwellings to meet relevant energy efficiency requirements in the building regulations. The guidance applies to the following types of oil-fired heating system:

• wet central heating systems

• range cookers with integral central heating boilers

• vaporising appliances providing secondary heating or hot water

• fixed independent space heating devices.

3.2Oil-fired wet central heating systems

New systems

New systems for oil-fired central heating in new and existing dwellings should meet the minimum standards for:

a.boiler efficiency, system circulation, hot water storage, system preparation and commissioning in Table 11

b.boiler interlock, zoning, and time and temperature control of the heating and hot water circuits in Table 12

c.pipework insulation in Table 14.

Work on existing systems

Components installed as replacements in existing systems should meet the same standards as for new systems, except where indicated otherwise in Table 13.

Table 13 in addition identifies good practice upgrades to the rest of the system when making planned and emergency replacements that go beyond the requirements of the building regulations.

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Table 11: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems

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Table 11: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems

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Table 11: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems

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Table 11: Recommended minimum standards for efficiency, system circulation, hot water storage, system preparation and commissioning for oil-fired wet central heating systems

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Table 12: Recommended minimum controls of oil-fired wet central heating systems

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Table 13: Recommended minimum standards when replacing components of oil-fired wet central heating systems

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Table 14: Recommended minimum standards for insulation of pipework in oil-fired wet central heating systems

3.3Oil-fired range cookers with integral central heating boilers

This section provides guidance on the specification of oil-fired range cookers with integral central heating boilers for space heating and hot water in dwellings.

Note: The guidance applies only to twin-burner cooker boilers, which should not be confused with the type of range cooker described as a single burner ‘dry heat’ range cooker. The latter is intended only to provide a cooking function, is not included in SAP 2012 calculations, and does not come within the scope of the building regulations energy efficiency requirements.

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Where oil-fired range cookers with an integral central heating boiler are provided as part of new systems or as replacement components in existing systems:

a.The appliance should have two independently controlled burners (one for the cooking function and one for the boiler).

b.The SEDBUK 2009 efficiency of the integral boiler should be not less than 80%.

c.The manufacturer’s declaration of appliance performance and SEDBUK value should include the following statement and information

i. Seasonal efficiency (SEDBUK) = xx% ii. Case heat emission value = yy kW iii. Heat transfer to water at full load = zz kW iv. The efficiency values may be used in the UK Government’s Standard Assessment Procedure (SAP) for the energy rating of dwellings. The test data from which they have been calculated has been certified by [insert name and/or identification of Notified body]. See www.rangeefficiency.org.uk.

If the integral boiler is a condensing boiler, the declaration should make clear whether the efficiency has been calculated in accordance with SEDBUK 2005 or SEDBUK 2009. If it does not, then SEDBUK 2005 must be assumed.

d.The integral boiler should meet the minimum standards for oil-fired central heating systems in Tables 11, 12 and 14 for system circulation, hot water storage, system preparation, commissioning, controls and insulation.

3.4Continuously-burning oil-fired vaporising appliances providing secondary heating or hot water

This section provides guidance on the specification of oil-fired vaporising appliances providing secondary heating or hot water for dwellings. The guidance does not apply to appliances which have been converted from another fuel (for example from solid fuel to oil).

Oil-fired vaporising appliances provided with new systems or as replacement components in existing systems should meet the minimum standards for controls in Table 15.

Table 15: Recommended minimum standards for control of continuously burning oil-fired vaporising appliances

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3.5Oil-fired fixed independent space heating appliances

This section provides guidance on the specification of oil-fired fixed independent appliances for primary or secondary space heating in dwellings.

Oil-fired fixed independent appliances for primary heating

Where oil-fired fixed independent space heating appliances are provided as the primary heat source in new dwellings:

a.The efficiency of the appliance (gross calorific value) should be not less than 60%. The appliance manufacturer’s declaration of appliance performance should include the following words:

The net efficiency of this appliance has been measured as specified in OFS A102:2004 and the result after conversion to gross using the appropriate factor from Table E4 of SAP 2012 is xx%. The test data has been certified by [insert name and/or identification of Notified Body]. The efficiency value may be used in the UK Government’s Standard Assessment Procedure (SAP) for energy rating of dwellings.

b.Each appliance should be capable, either independently or in conjunction with room thermostats or other suitable temperature sensing devices, of controlling the temperatures independently in areas that have different heating needs (e.g. separate sleeping and living areas).

Oil-fired fixed independent appliances for secondary heating

Oil-fired fixed independent space heating appliances in new dwellings which are provided as the secondary heat source should have an efficiency (gross calorific value) of not less than 60%.

3.6Supplementary Information

Energy Efficiency Best Practice in Housing publications:

CE29 – ‘Domestic heating by oil: boiler systems’.

CE51 – ‘Central heating system specifications (CHeSS)’.

CE54 – ‘Whole house boiler sizing method for houses and flats’.

OFTEC Technical Books 2, 3, 4 and 5 (see www.oftec.org)

BS EN 12828:2012 – ‘Heating systems in buildings. Design for water-based heating systems’.

BS 5410-1:1997 – ‘Code of practice for oil firing installations up to 45kW output capacity for space heating and hot water supply purposes’.

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4.1Scope of guidance

This section provides guidance on the specification of fixed electric heating systems for dwellings to meet relevant energy efficiency requirements in the building regulations. The guidance given in this section covers the following types of fixed electric heating systems:

• electric boilers serving central heating systems

• electric warm air systems

• electric panel heaters

• electric storage systems including integrated storage/direct systems.

Portable, plug-in appliances are not covered by the building regulations or by this guide.

4.2Electric boilers serving central heating systems

Electric boilers serving wet central heating provided with new systems or as replacement components in existing systems should meet the minimum standards for:

a.system circulation, system preparation and commissioning in Table 16

b.boiler interlock, zoning, and time control and temperature control of heating and hot water circuits in Table 17

c.hot water storage systems in Table 18

d.pipework insulation in Table 19.

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Table 16: Recommended minimum standards for system circulation, preparation and commissioning for electric wet central heating systems

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Table 17: Recommended minimum standards for control of electric wet central heating systems

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Table 18: Recommended minimum standards for hot water storage in electric wet central heating systems

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Table 18: Recommended minimum standards for hot water storage in electric wet central heating systems

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Table 19: Recommended minimum standards for insulation of pipework in central heating systems with electric boilers

4.3Electric heating systems (other than electric boilers for central heating)

This section provides guidance on the following types of fixed electric heating systems:

• electric warm air systems

• electric panel heaters

• electric storage systems including integrated storage/direct systems.

Portable, plug-in appliances are not covered by this guide.

Fixed electric heating systems (other than with electric boilers) should meet the minimum standards for time and temperature control in Table 20.

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Table 20: Recommended minimum standards for control of primary and secondary electric heating systems (other than with electric boilers)

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5.1Scope of guidance

This section provides guidance on meeting the energy efficiency standards in the building regulations for the following types of solid fuel heating appliances and systems used to deliver primary and secondary heating:

• batch-fed open fires

• batch-fed and automatic-feed dry room heaters/stoves

• batch-fed log and multi-fuel appliances

• automatic-feed pellet stoves with and without boilers

• batch-fed and automatic-feed room heaters with boilers

• batch-fed cookers with boilers not exceeding 7.5kW

• batch-fed independent boilers and automatic-feed anthracite, wood pellet, wood chip and wood log fired independent boilers

• central heating systems using certain types of solid fuel appliances.

The guidance covers the following types of solid fuel: coal, anthracite, manufactured smokeless fuel, dual-fuel, wood logs, wood pellets and wood chips.

5.2Solid fuel appliances for primary heating

Solid fuel appliances provided as part of new systems or as a replacement appliance in existing systems for primary heating in dwellings should have an efficiency (gross calorific value) not less than specified in Table 21 for that category of appliance.

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Table 21: Solid fuel appliance categories and recommended minimum efficiencies

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5.3Central heating systems using certain types of solid fuel appliances

This section provides guidance on the following types of solid fuel appliance used to deliver primary heating as part of a central heating system:

• batch-fed open fires with high output boilers (appliance types D1 to D4 in Table 21)

• batch-fed and automatic-feed room heaters and stoves with boilers (appliance type F in Table 21)

• batch-fed cookers with boilers (appliance type G2 in Table 21)

• batch-fed independent boilers and automatic-feed anthracite, wood log, wood pellet and wood chip-fired independent boilers (appliance types J1 to J5 in Table 21).

Unless stated otherwise, the guidance applies equally to appliances that burn wood, wood pellets, house coal, manufactured smokeless fuels and anthracite.

For central heating systems with a solid fuel appliance installed as part of a new system or as a replacement component in an existing system:

a.the appliance should be from HETAS categories D, F, G and J in Table 21 and have a minimum efficiency (gross calorific value) which is not less than the value specified for its category

b.the ratio of room heat to water heat should be appropriate for the room and total property. This will require reference to installation practice guidelines and calculation of room and property heat loss. Advice on this is given in the HETAS Guide and website

c.circulation, fuel storage, hot water storage, system preparation, water treatment and commissioning should be to the standards in Table 22

d.control of heating and hot water circuits should be to the standards in Table 23

e.pipework should be insulated to the standards in Table 24.

Supplementary information

Turn-down values (i.e. the ratio of high to low output)

Turn-down ratios are generally very good (>10:1) for automatic-feed appliances with small firebeds.

Turn-down ratios are poorer with large batch-fed appliances unless the latter are used in conjunction with a hot water accumulator.

Automatic appliances are likely to require less frequent refuelling. Automatic (e.g. electric or gas) ignition is now available for certain designs and reduces energy usage at times of low demand allowing boiler interlock.

Some boilers have both auto-ignition and fire-extinguishing features.

Link-up systems

It is possible to connect together two or more heating appliances with boilers (at least one of which can be solid fuel-fired), to maximise flexibility and efficiency. For example, an oil or gas boiler could be combined with a wood burning stove with boiler sited in the living room. This combination with wood burning appliances will reduce overall carbon emissions. Both systems should be designed to appropriate installation codes.

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Table 22: Recommended minimum standards for system circulation, fuel storage, hot water storage, system preparation and commissioning for solid fuel central heating

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Table 22: Recommended minimum standards for system circulation, fuel storage, hot water storage, system preparation and commissioning for solid fuel central heating

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Table 23: Recommended minimum standards for control of solid fuel central heating systems

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Table 24: Recommended minimum standards for insulation of pipework in solid fuel central heating systems

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5.4Solid fuel appliances for secondary heating

Solid fuel appliances in new and existing dwellings that provide secondary heating and are not part of a central heating system should have the minimum efficiency (gross calorific value) specified in Table 21 for the category of appliance.

Supplementary information

Minimum efficiencies

Minimum efficiencies for solid fuel appliances are published in the HETAS ‘Official guide to approved solid fuel products and services’, and on the website www.hetas.co.uk. Manufacturers’ figures may be higher but should be used only where independently certified against the harmonised European Standards now in place.

Appliance types

The types of appliance most suitable for providing secondary heating are:

• Open-fire with high output boiler, when used with ‘link-up’

• Small solid fuel room heaters (stoves), especially wood-fired

These can be a dedicated wood burner or burn logs in a multi-fuel appliance or use pellets. They can be matched with a main heating system fired by the same or a different primary fuel or off-peak electricity to reduce carbon emissions, especially wood-fired, with or without thermostatic control. Many designs can provide heating during power cuts. Mineral fuel appliances can be chosen but the attention of designers is drawn to the probable need to supply additional measures, as the carbon emission values of these tend to be high. Mineral fuel appliances may often have slightly higher efficiencies than their wood burning counterparts. Multi-fuel room heaters can enable the user to burn renewable wood as well as an alternative to mineral fuels outside smoke control areas.

• Small solid fuel stoves with boilers

The efficiency of these can be higher than that of dry appliances. They can be integrated with the primary wet heating system. Multi-fuel appliances enable the householder to burn renewable wood outside smoke control areas.

• Range cookers

Typically appliances which are installed in a ‘living area’ and are designed to provide some useful heat from their case into the space in which they are located. They are available in a variety of shapes and sizes and can incorporate a boiler which can be connected to dual-fuel integrated systems (e.g. link-up). Multi-fuel versions are also available.

• Open fires (HETAS categories B1, B2 and B3)

Where requested, these can be fitted. They do not have thermostatic control of the burning rate and so have lower efficiencies, but they are able to burn wood logs with correspondingly low net carbon emissions. It must be stressed that large open fires with a large free face area (opening width times opening height) usually have a need for ventilation well in excess of that available in a property built to modern standards of air tightness. This is likely to lead to severe operational problems unless special steps are taken to provide the required air supply. The use of such large (simple) open fires is penalised in the SAP calculations.

Controls

Wherever possible, solid fuel appliances should have thermostatic control. (These are usually integral to appliances in categories E, F and G.) Controls should be appropriate to the level of sophistication of the appliance; automatic appliances can benefit from advanced controls.

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Provision of fuel storage

The quantity of fuel consumed by secondary heating appliances is likely to be less than 1 tonne per year. However it should be stored in a dry and convenient location.

Smoke control areas

The location of the appliance within or without a smoke control area is critical to the process of optimising the choice of appliance and fuel.

For further information on solid fuel appliances, see CE47 –‘Energy Efficiency Best Practice in Housing – Domestic heating by solid fuel: Boiler systems’.

Standards

BS EN 12809:2001 + A1:2004 + AC: 2006/2007 – ‘Residential Independent boilers fired by solid fuel. Nominal output up to 50kW. Requirements and test methods’.

BS EN 12815:2001 A1:2004/2006/2007 – ‘Residential cookers fired by solid fuel. Requirements and test methods’.

BS EN 13229:2001 + A1:2003/ A2:2004 + AC:2006/2007 – ‘Inset appliances including open fires fired by solid fuel. Requirements and test methods’.

BS EN 13240:2001 +A2:2004 + AC2006/2007 – ‘Room heaters fired by solid fuel. Requirements and test methods’.

BS EN 15250:2007 – ‘Slow heat release appliances fired by solid fuel. Requirements and test methods’.

BS EN 15544:2009 – ‘One-off tiled/ mortared stoves – Calculation method’.

BS EN 14785:2006 - Residential space heating appliances fired by wood pellets’.

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6.1Scope of guidance

This section provides guidance on the specification of community heating systems for dwellings to meet relevant energy efficiency requirements in the building regulations.

A community heating system is one that supplies heat to a number of dwellings from a common heat source. A system may heat a small block of flats or a large number of buildings.

The guidance in this section applies to systems that:

• supply 15 or more dwellings from a central boiler, or from a low carbon source such as combined heat and power (CHP), biofuels, heat pumps and solar panels

• distribute heat from the central source using a wet radiator system (although warm air heating and underfloor heating systems may also be used).

Metering requirements for community heating schemes are being introduced, starting in June 2014, as a result of the EU Energy Efficiency Directive. See the DECC website16 for details of the requirements and the technical standards that apply (for example on meter specifications).

6.2New and existing community heating schemes

The central heat source should comply with the requirements in the Non-domestic Building Services Compliance Guide for Scotland17 except where specified in this section.

Guidance is provided for two scenarios:

• connecting dwellings to a new community heating scheme

• connecting dwellings to an existing community heating scheme.

Connecting dwellings to a new community heating scheme

New community heating systems for both new and existing dwellings should meet the minimum standards for:

a.energy efficiency in Table 25

b.low-carbon heat sources in Table 26

c.system control in Table 27

d.hot water production, storage and treatment, heat metering and commissioning in Table 28

e.insulation of pipework in Table 29.

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Connecting dwellings to an existing community heating scheme

Where existing community heating systems are connected to new or existing dwellings:

a.If the existing community heating system is in need of replacement or improvement, a study should be carried out to assess the economic and environmental benefits of a range of options, including the use of CHP and other low carbon heat sources, especially where individual heating systems are being considered as an alternative to continuing with the community heating system.

b.Replacement boilers should meet the minimum standards for boiler efficiency in the Non-domestic Building Services Compliance Guide for Scotland.

c.If thermal energy is purchased from an existing district or community heating system, an assessment of the carbon intensity of the scheme should be carried out. Emission factors should be determined based on the particular details of the scheme, but should take account of the annual average performance of the whole system – that is, of the distribution circuits and all the heat generating plant, including any CHP, and any waste heat recovery or heat dumping. The calculation of the Dwelling CO2 Emission Rate should be carried out by a person who is familiar with the calculation methodology and can explain how the emission factors were derived.

d.Controls should meet the minimum standards in Table 27.

e.Pipework insulation should meet the minimum standards in Table 29 and Table 30.

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Table 25: Recommended minimum standards for the design of new community heating systems to maximise efficiency of heat generation and minimise energy use by pumps

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Table 26: Recommended minimum standards for design of low-carbon heat sources where these are included in community heating systems

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Table 27: Recommended minimum standards for control of systems within dwellings for community heating

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Table 27: Recommended minimum standards for control of systems within dwellings for community heating

Table 28: Recommended minimum standards for domestic hot water production, storage and water treatment, heat meters and commissioning for community heating

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Table 28: Recommended minimum standards for domestic hot water production, storage and water treatment, heat meters and commissioning for community heating

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Table 29: Recommended minimum standards for insulation of internal pipework in community heating systems

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Table 30: Recommended minimum standards for insulation of external pipework in community heating systems

Supplementary information

Good Practice Guide GPG234 – ‘Guide to community heating and CHP – Commercial, public and domestic applications’. Available from the Carbon Trust.

BS EN 13941:2009 + A1 2010 – ‘Design and installation of pre-insulated bonded pipe systems for direct heating’.

BS EN 14419:2009 – ‘District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Surveillance systems’.

BS EN 253:2009 + A1:2013 – ‘District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Pipe assembly of steel service pipe, polyurethane thermal insulation and outer casing of polyethylene’.

BS EN 448:2009 – ‘District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Fitting assemblies of steel service pipes, polyurethane thermal insulation and outer casing of polyethylene’.

BS EN 488:2011 – ‘District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Steel valve assembly for steel service pipes, polyurethane thermal insulation and outer casing of polyethylene’.

BS EN 489:2009 – ‘District heating pipes. Pre-insulated bonded pipe systems for directly buried hot water networks. Joint assembly for steel service pipes, polyurethane thermal insulation and outer casing of polyethylene’.

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7.1Scope of guidance

This section provides guidance on the specification of underfloor heating systems in new dwellings to meet relevant energy efficiency requirements in the building regulations.

The guidance covers the use of hot water pipes or electric heating elements as the underfloor heat source.

7.2Underfloor heating in new dwellings

Underfloor heating in new dwellings should meet the minimum standards for:

a.system control and safe operating temperatures in Table 31

b.floor insulation and system design to minimise distribution losses in Table 32

c.in the case of electric underfloor heating systems in new dwellings, construction and controls in Table 33.

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Table 31: Recommended minimum standards for control of wet and electric underfloor heating systems

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Table 32: Recommended minimum standards for floor insulation and minimising distribution losses in wet and electric underfloor heating systems

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Table 32: Recommended minimum standards for floor insulation and minimising distribution losses in wet and electric underfloor heating systems

Table 33: Recommended minimum standards for construction and control of electric underfloor heating systems

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Table 33: Recommended minimum standards for construction and control of electric underfloor heating systems

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8.1Scope of guidance

This section provides guidance on the specification of mechanical ventilation systems in dwellings to meet relevant energy efficiency requirements in the building regulations.

The guidance covers the following types of mechanical ventilation:

• intermittent extract

• continuous extract

• continuous supply

• continuous supply and extract with heat recovery.

8.2Energy efficiency of mechanical ventilation systems

Mechanical ventilation systems should:

a. follow the guidance in Building Standards Division ‘Domestic Ventilation Guide’ - http://www.scotland.gov.uk/Topics/BuiltEnvironment/Building/Buildingstandards/te chbooks/techhandbooks/domventguide;

b.meet the minimum standards for specific fan power, heat recovery efficiency and controls in Table 34; and

c.comply with European Commission Regulation No 327/2011 implementing Directive 2009/125/EC with regard to ecodesign requirements for fans driven by motors with an electric input power between 125 W and 500 kW.

Table 34: Recommended minimum standards for mechanical ventilation systems

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9.1Scope of guidance

This section provides guidance on the specification of heat pump systems in dwellings for the provision of space heating and domestic hot water to meet relevant energy efficiency requirements in the building regulations.

A heat pump is a device which takes heat energy from a low temperature source and upgrades it to a higher temperature at which it can be usefully employed for heating or hot water. Heat pumps may supply all or part of the heating load.

The guidance in this section applies to the types of electrically-driven heat pump in Table 35 used as the heat generator in underfloor, warm air and medium temperature radiator heating systems, etc.

Table 35: Heat pump technologies

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Supplementary information

All heat pump systems are at their most efficient when the source temperature is as high as possible, the heat distribution temperature is as low as possible and pressure losses in air and water systems are kept to a minimum. If installed in a new dwelling, heat pumps should use refrigerants complying with the provisions of EU Directive 2037:2000. Heat pumps should be CE marked in accordance with applicable EU Directives: e.g. the machinery safety, low voltage, pressure equipment and electromagnetic compatibility Directives. If summer cooling is provided by the heat pump, it is recommended that condensate drainage from the indoor units is provided.

9.2Key terms

Coefficient of performance (COP) is a measure of the efficiency of a heat pump at specified source and sink temperatures, but may not accurately represent installed performance:

Heating COP = heat output / power input

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

COP is measured in accordance with the procedures in EN 14511:2013, Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling.

Seasonal coefficient of performance (SCOP) is the overall coefficient of performance of the heat pump over the designated heating season. It makes general assumptions about the amount of auxiliary heating needed to top up the space and water heating available from the heat pump.

SCOP is measured in accordance with the procedures in BS EN 14825:2013 – ‘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’.

The National Calculation Methodology for calculating carbon dioxide emission rates from buildings uses SCOP.

Seasonal performance factor (SPF) is another measure of the operating performance of an electric heat pump over the season. It is the ratio of the heat delivered to the total electrical energy supplied over the season, but there are seven different ways to draw the system boundaries. For example, SPFH2 (which is SCOP) excludes auxiliary resistance heating whereas SPFH4 includes it – making a large difference.

SAP 2012 calculations use SPF – either measured values for products listed in the Product Characteristics Database, or the default values in Table 4a for products not listed there.

The Microgeneration Certification Scheme installation standard MIS 3005 uses SPF to calculate system performance (although the heat pump product standard, MCS 007, currently specifies a minimum COP).

Seasonal primary energy efficiency ratio (SPEER) is an emerging rating figure reflecting the use of primary energy for all types of heat pump, fossil fuel boiler and gas-driven cogeneration technologies, as well as hybrid systems where solar heating or a heat pump is backed up with electric heating or a fossil fuel boiler.

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Energy labelling with the SPEER will be mandatory from 2015 under the Energy Labelling Directive. Testing and rating will be in accordance with EN 14825, as for SCOP.

9.3Warm water and hot water heat pumps

At the time of preparation of this guide, European Commission Regulation No 206/2012 sets standards for the SCOP of electrically-driven air-to-air heat pumps with an output ≤ 12 kW. There are currently no European test standards for part-load testing of air-to-air heat pumps with an output > 12 kW or for other types of heat pump, and the performance of these must be specified using COP obtained at the heating system rating conditions.

The current recommendations in this guide, therefore, are that electrically-driven heat pumps should:

a.if air-to-air with an output ≤ 12 kW, have at least a SCOP ‘D’ rating for the median temperature range in EN 14825

b.or else have a COP which is not less than:

i.2.5 for space heating in new dwellings

ii.2.2 for space heating in existing dwellings

iii.2.0 for heating domestic hot water

c.meet the minimum standards for supply temperature, wet system radiator efficiency, installation and commissioning, hot water and controls in Table 36 for warm water and hot water heat pumps

d.meet the minimum standards for installation and controls in Table 37 for warm air heat pumps.

Table 36: Recommended minimum standards for warm water and hot water heat pumps (ground-to-water, water-to-water and air-to-water systems)

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Table 36: Recommended minimum standards for warm water and hot water heat pumps (ground-to-water, water-to-water and air-to-water systems)

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Table 36: Recommended minimum standards for warm water and hot water heat pumps (ground-to-water, water-to-water and air-to-water systems)

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Table 37: Recommended minimum standards for warm air heat pumps (ground-to-air, water-to-air and air-to-air systems)

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Supplementary information

Guidance

Microgeneration Certification Scheme standard MIS 3005 – ‘Requirements for contractors undertaking the supply, design, installation, set to work, commissioning and handover of microgeneration heat pump systems’.

Microgeneration Certification Scheme standard MIS 3007 – ‘Product certification scheme requirements – heat pumps’.

‘Heat emitters guide for domestic heat pumps’, available from http://www.microgenerationcertification.org/mcs-standards/installer-standards

CE 82 – ‘Energy Efficiency Best Practice in Housing: Domestic ground source heat pumps: design and installation of closed-loop systems’.

Heat Pump Association data sheet – ‘Air-to-water heat pumps’.

HVCA TR30 – ‘Guide to good practice: Heat pumps’.

British and European Standards

BS EN 15450:2007 – ‘Heating systems in buildings. Design of heat pump heating systems’.

BS EN 15316-4-2:2008 – ‘Heating systems in buildings. Method for calculation of system energy requirements and system efficiencies. Space heating generation systems, heat pump systems’.

BS EN 378-1 2008 +(A1)(A2):2012 – ‘Refrigerating systems and heat pumps. Safety and environmental requirements and system efficiencies - Basic requirements, definitions, classifications and selection criteria’

BS EN 378-2 2008 +(A1)(A2):2012 – ‘Refrigerating systems and heat pumps. Safety and environmental requirements and system efficiencies - Design, construction, testing, marking and documentation’.

BS EN 378-3 2008 +(A1)(A2):2012 – ‘Refrigerating systems and heat pumps. Safety and environmental requirements and system efficiencies - Installation site and personal protection’.

BS EN 378-4 2008 +(A1)(A2):2012 – ‘Refrigerating systems and heat pumps. Safety and environmental requirements and system efficiencies - Operation, maintenance, repair and recovery’

ISO 13256-1: 1998 – ‘Water-source heat pumps. Testing and rating for performance - Water-to-air and brine-to-air heat pumps’.

ISO 13256-1: 1998 – ‘Water-source heat pumps. Testing and rating for performance - Water-to- water and brine-to-water heat pumps’.

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10.1Scope of guidance

This section provides guidance on the specification of fixed mechanical comfort cooling systems and fans in dwellings to meet relevant energy efficiency requirements in the building regulations.

(Dwellings should always be designed to avoid or minimise the need for cooling through the appropriate use of solar control, secure ventilation and thermal mass).

10.2Air-cooled and water-cooled air conditioners

Cooling systems in new and existing dwellings should:

a.meet the minimum standards for efficiency in Table 38

b.be controlled to prevent simultaneous heating and cooling of the same space within the dwelling

c.comply with European Commission Regulation No 327/2011 for fans driven by motors with an electric input power between 125 W and 500 kW, and Regulation No 206/2012 for systems with a cooling capacity of up to 12 kW, both implementing Directive 2009/125/EC with regard to ecodesign requirements for energy-related products.

Table 38: Recommended minimum standards for comfort cooling

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11.1Scope of guidance

This section provides guidance on the specification of solar water heating for dwellings to meet relevant energy efficiency requirements in the building regulations.

The guidance in this section covers indirect solar systems with a collector area of less than 20 m2 and solar heated water storage of less than 440 litres. It does not cover ‘direct’ solar systems18 or systems intended to contribute exclusively to space heating or systems providing heat exclusively to heat swimming pools. It should be used in conjunction with the guidance on water heating contained in the fuel-based sections of this guide.

11.2Indirect systems

Indirect solar heating systems installed as new systems and replacement systems should meet the minimum standards for:

a.collector certification, identification and testing, collector primary loop transfer fluid, circulation pump power, heat-exchanger sizing, system control, solar pre-heated water storage, and system preparation in Table 39

b.system labelling and commissioning in Table 40

c.insulating pipes in a solar primary system in Table 41.

Supplementary information

When work is carried out on an existing indirect solar hot water system, it is recommended that the system controls and insulation should be upgraded in line with the standards for new systems.

Table 39: Recommended minimum standards for indirect solar water heating

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Table 39: Recommended minimum standards for indirect solar water heating

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Table 39: Recommended minimum standards for indirect solar water heating

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Table 39: Recommended minimum standards for indirect solar water heating

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Table 40: Recommended minimum standards for labelling, commissioning and documentation for solar hot water systems

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Table 40: Recommended minimum standards for labelling, commissioning and documentation for solar hot water systems

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Table 41: Recommended minimum standards for insulation of pipework in solar hot water systems

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Supplementary Information

Further guidance and standards

Microgeneration Certification Scheme standard MIS3001 - ‘Requirements for contractors undertaking the supply, design, installation, set to work, commissioning and handover of solar heating microgeneration systems’.

Energy Efficiency Best Practice in Housing CE131 – ‘Solar water heating systems. Guidance for professionals, conventional indirect models’.

CIBSE ‘Solar heating design and installation guide’.

CE 51/GIL59 – ‘Central Heating System Specifications’ (CHeSS), 2005.

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12.1Scope of guidance

This section provides guidance on the specification of fixed internal and external lighting for new and existing dwellings to meet relevant energy efficiency requirements in the building regulations.

12.2Key terms

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

Light fitting means a fixed light or lighting unit that can comprise one or more lamps and lampholders, control gear and an appropriate housing. The control gear may be integrated in the lamp or located elsewhere in or near to the fixed light.

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

12.3Internal and external lighting

Fixed internal and external lighting should meet the minimum standards for efficacy and controls in Table 42.

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Table 42: Recommended minimum standards for fixed internal and external lighting

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Supplementary information

British and European Standards

BS EN 15193:2007 – ‘Energy performance of buildings – Energy requirements for lighting’.

Other related documents

CE80 – ‘Domestic lighting innovations’, Energy Efficiency Best Practice in Housing.

CE61 – ‘Energy efficient lighting – guidance for installers and specifiers’, Energy Saving Trust.

EP84 – ‘Housing for people with sight loss’, Thomas Pocklington Trust Design Guide.

IP412 – ‘Making the most of your sight: Improve the lighting in your home’, RNIB and Thomas Pocklington Trust.

Energy Saving Trust best practice standards

The Energy Saving Trust sets best practice ‘Energy Saving Recommended’ (ESR) standards for lamps that cover not only energy efficiency, but also other aspects of quality including colour rendering, warm-up time, product life and power factor. It is advisable to install only ESR low energy lamps in dwellings.

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13.1Scope of guidance

This section provides guidance on the specification of micro-combined heat and power (micro-CHP) packages for dwellings to meet relevant energy efficiency requirements in the building regulations.

The guidance covers micro-CHP systems with an electrical output less than 5 kWe which are:

• heat-led

• capable of exporting electricity to the grid, and

• controlled in such a way as to avoid heat dumping.

13.2Key terms

Heating plant emission rate (HPER) is the annual CO2 emissions from fuel and power consumed by the heating plant, offset by the emissions saved as a result of any electricity generated by the heating plant, divided by the heat output over a year. It is measured in units of kg of CO2 per kWh. To calculate HPER it is necessary to know the plant size ratio.

Note: The HPER includes any auxiliary space and water heating that may be necessary, i.e. it represents the performance of all heating plant needed to provide space and water heating service to the building, assuming a standard demand pattern.

Plant size ratio (PSR) is defined as the nominal heat output of the heating plant divided by the design heat loss (the average heat loss of the building on a cold day with a temperature differential of 24.2 °C). Note: For a given heat demand, the PSR determines the part-load condition for the heating plant.

13.3Micro-CHP systems

a.For new systems and alterations to existing systems, the HPER of the micro-CHP package (calculated as in sub-paragraph c. below) should be no greater than the carbon emission factor for the fuel divided by the minimum efficiency for a regular boiler using that fuel, at the PSR determined as in sub-paragraph b. below. The design heat loss of the dwelling should be calculated using the Energy Saving Trust’s Whole house boiler sizing method for houses and flats19.

b.The PSR for the micro-CHP system when operating in the intended dwelling should be calculated as defined in paragraph 13.2 above.

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c.The HPER of the micro-CHP system should be calculated at the PSR determined in sub- paragraph b. above, using the methodology set out in DECC’s Annual Performance Method (APM)20, and the performance data for the micro-CHP package established by testing according to BSI PAS 6721.

Supplementary information

British and European Standards

BS EN 15316-4-4:2007 – ‘Heating systems in buildings – method for calculation of system energy requirements and system efficiencies – Heat generation systems, building-integrated cogeneration systems’.

Other documents

Appendix N of SAP 2012 - ‘Method to evaluate the annual energy performance of micro- cogeneration heating systems in dwellings’.

BSRIA BG 2/2007 – ‘CHP for existing buildings: Guidance on design and installation’.

Microgeneration Certification Scheme standard, MIS 3007-2 – ‘Requirements for contractors undertaking the design, supply, installation, set to work, commissioning and handover of a domestic hot water system containing an electricity-led micro-cogeneration package’.

‘Connecting a microgeneration system to a domestic or similar electrical installation (in parallel with the mains supply)’, Best Practice Guide, the Electrical Safety Council.

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14.1Scope of guidance

This section provides guidance on the specification of heating system glandless circulators, both standalone and integrated in products, to meet relevant energy efficiency requirements in the building regulations.

14.2Circulators

Heating system glandless circulators up to 2.5 kW, provided with new systems or as replacements in existing systems in dwellings, should meet the minimum standards for energy efficiency in Table 43.

Table 43: Recommended minimum standards for glandless heating system circulators

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APM Annual Performance Method

ASHP Air Source Heat Pump

BS British Standard

BSD Building Standards Division

BSI British Standard Institute

CHeSS Central Heating System Specification

CHP Combined Heat And Power

CO2 Carbon Dioxide

COP Coefficient Of Performance

DECC Department For Energy And Climate Change

DHW Domestic Hot Water

EEI Energy Efficiency Index

EER Energy Efficiency Ratio

EN European Norm (Standard)

ESR Energy Saving Recommended

GSP Ground Source Heatpump

HPER Heating Plant Emission Rate

HVAC Heating Ventilation And Air Conditioning

LPG Liquefied Petroleum Gas

PAS Publicly Available Specification

PCDB Product Characteristic Database

PSR Plant Size Ratio

RHI Renewable Heat Incentive

SAP Standards Assessment Procedure

SCOP Seasonal Coefficient Of Performance

SG Scottish Government

SEDBUK Seasonal Efficiency Of Domestic Boilers In The UK

SEER Seasonal Energy Efficiency Ratio

SFP Specific Fan Power

SI Statutory Instrument

SPEER Seasonal Primary Energy Efficiency Ratio

SPF Seasonal Performance Factor

TER Target (Carbon Dioxide) Emission Rate

TRV Thermostatic Radiator Valve

WSHP Water Source Heat Pump

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