Planning circular 1/2024: householder permitted development rights

6. Installing Microgeneration Equipment

6.1 This section explains the PDR for the following types of domestic microgeneration equipment:

• Ground and Water Source Heat Pumps (Class 6D and 6E)
• Air Source Heat Pumps (Class 6H)
• Free-Standing Wind Turbines (Class 6G)
• Roof-Mounted Wind Turbines on Detached Dwellinghouses (Class 6HC)
• Solar panels on a dwelling (Class 6HA)
• Solar panels on a building within the curtilage of a dwelling (Class 6HB)
• Flues for Biomass Heating Systems (Class 6C) and Combined Heat and Power Systems (Class 6F)

6.2 Free-standing solar panels within the curtilage of a dwellinghouse are covered by Class 3B.

6.3 All the limitations and restrictions within a class will need to be complied with in order for a development to benefit from the PDR granted by that class.

Ground or Water Source Heat Pumps (Class 6D and 6E)

6.4 PDR allow the installation, alteration or replacement of a Ground Source Heat pump or Water Source Heat pump within the curtilage of a dwellinghouse or a building containing a flat. The PDR apply both to the pump itself and to any associated equipment and pipework. There are no additional restrictions on those PDR.

Legislation

Class 6D.- The installation, alteration or replacement of a ground source heat pump and any associated pipes or apparatus within the curtilage of a dwellinghouse or building containing a flat.

Class 6E.- The installation, alteration or replacement of a water source heat pump and any associated pipes or apparatus within the curtilage of a dwellinghouse or building containing a flat.

Air Source Heat Pumps (Class 6H)

6.5 Class 6H permits the installation, alteration or replacement of an air source heat pump (ASHP) on a dwelling or within the curtilage of a dwelling. In both cases, this means a dwellinghouse, a building containing one or more flats or a flat contained within such a building.

6.6 The aim of these provisions is to manage adverse impacts on neighbours and amenity generally (e.g. noise and visual impact) set against the wider environmental, social and economic benefits of microgeneration. They do this by means of limitations and conditions.

Limitations

6.7 For ASHP, the limitations are that:

• a development is not permitted if it would result in more than one ASHP on the same building or within the curtilage of a building.
• development is not permitted if it would result in the protrusion of an ASHP by more than 1 metre from the outer surface of an external wall, roof plane, roof ridge or chimney of a dwelling.
• development is not permitted on a dwelling within a Conservation Area unless the ASHP is located at ground floor level and on the rear elevation of the dwelling.
• development is not permitted within the curtilage of a building if any part of the installation would be forward of a wall forming part of the principal or side elevation of a building where that elevation fronts a road, or if any resulting ASHP structure would exceed 3 metres in height.
• development is not permitted in a World Heritage Site or within the curtilage of a listed building.

Conditions

6.8 The conditions require that ASHP microgeneration equipment only be used for domestic microgeneration purposes, and that an ASHP only be used for the purpose of providing domestic heating or hot water. ASHP equipment must be removed as soon as reasonably practicable where it is no longer needed for, or capable of, being used for these purposes.

6.9 A further condition of the PDR is that the equipment installed must comply with MCS 020 planning standards for air source heat pumps or equivalent standards.

Legislation

Class 6H

(1) The installation, alteration or replacement of an air source heat pump on a dwelling or within the curtilage of a dwelling.

(2) Development is not permitted by this class—

(a) if it would result in the presence on the same building or within the curtilage of a building of more than one air source heat pump;

(b) in the case of an installation, alteration or replacement of an air source heat pump on a dwelling if—

(i) any part of the development would protrude more than 1 metre from the outer surface of an external wall, roof plane, roof ridge or chimney of the dwelling; or

(ii) the air source heat pump would be within a conservation area, unless the air source heat pump would be—

(aa) at ground floor level; and

(bb) on the rear elevation;

(c) in the case of the installation, alteration or replacement of an air source heat pump within the curtilage of a building if—

(i) any part of the development would be forward of a wall forming part of the principal elevation or side elevation where that elevation fronts a road; or

(ii) any resulting structure would exceed 3 metres in height; or

(d) the air source heat pump would be within—

(i) a World Heritage Site; or

(ii) the curtilage of a listed building.

(3) Development is permitted by this class subject to the following conditions—

(a) the air source heat pump must be used only for the purpose of providing domestic heating or hot water;

(b) where the air source heat pump is no longer needed for, or capable of, providing domestic heating or hot water it must be removed as soon as reasonably practicable;

(c) the air source heat pump must comply with MCS Planning Standards for air source heat pumps or equivalent standards.

Free-standing Wind Turbines (Class 6G)

6.10 Class 6G permits the installation, alteration or replacement of a free-standing wind turbine within the curtilage of a dwelling.

6.11 The limitations are that:

• the installation of a free-standing wind turbine must be not less than 110% of the blade tip height from the curtilage of another dwelling.
• the blade tip height must not exceed 15m and the lowest part of the turbine blade must be at least 5m from the ground level.
• only one free-standing wind turbine is permitted within the curtilage of a dwelling.
• development is not permitted within a conservation area, a World Heritage Site, a site of special scientific interest, a site of archaeological interest, or within the curtilage of a listed building.

Conditions

6.12 The conditions are:

• the turbine, including the blades, must be constructed and maintained in a uniform external colour and must be kept free of rust, staining or other discolouration.
• The turbine must comply with the relevant MCS planning standards for wind turbines or equivalent standards.
• If the turbine is no longer needed or is incapable of generating electricity it must be removed as soon as is reasonably practical.
• Prior notification and approval procedures must be completed before development commences.

The prior notification and prior approval condition

6.14 The purpose of prior approval for micro-wind turbines is to allow the planning authority to consider any matter it may deem relevant in respect of the design, size, siting and external appearance of the proposed wind turbine. However, it is intended principally to provide a safeguard for aerodromes, radar technical sites, radio and television networks and National Scenic Areas (NSAs) that could be affected by wind turbine installations.

6.15 Aerodromes and radar technical sites are safeguarded by the Town and Country Planning (Safeguarded Aerodromes, Technical Sites and Military Explosive Storage Areas) (Scotland) Direction 2003. Circular 2/2003: safeguarded aerodromes, tech sites and storage areas contains the Direction and explains what consultation is required by planning authorities when an application for planning permission for development is made which could affect such a site. Certain military technical sites owned by the Secretary of State for Defence are also safeguarded under a similar process.

6.16 The operators of safeguarded aerodromes, technical sites and military explosives storage areas are also likely to need to examine specific proposals with particular reference to matters such as siting, design (including height), external appearance and type of construction when planning authorities consider applications for approval required by conditions attached to a grant of planning permission in principle. Although these are not applications for planning permission, and are therefore not covered by the Direction, Circular 2/2003 explains that planning authorities should as a matter of good practice consult the relevant consultees when they receive such applications and allow the consultees sufficient time to consider the implications for their operations before taking decisions on them.

6.17 It is considered therefore that as a conclusion of that good practice the same consultation procedure should apply where the planning authority's prior approval of a micro-wind turbine installation is sought.

Consultation - Further guidance

6.18 Additional guidance on aerodrome and technical sites safeguarding from obstacles including wind turbines is provided within Circular 2/2003: safeguarded aerodromes, tech sites and storage areas

6.19 For terrestrial radio and television networks the planning authority may consider it necessary to consult with the electronic communications provider or Ofcom to safeguard signal broadcasts from main sites or from relay sites typical of rural settings.

6.20 It would also be open to the planning authority and prospective developer to negotiate away any issues of concern, including submitting revised proposals as opposed to appeals or local reviews being pursued.

Removal condition

6.21 In instances where free-standing wind turbine equipment is no longer needed, or the equipment becomes incapable of being used, for example through breakdown that cannot be or is not repaired, the condition requires that it must be removed as soon as reasonably practicable. The removal condition is otherwise self-explanatory.

Legislation

Class 6G

(1) The installation, alteration or replacement of a free standing wind turbine within the curtilage of a dwelling.

(2) Development is not permitted by this class—

(a) if it would result in the presence within the curtilage of a dwelling of more than one free standing wind turbine,

(b) if the wind turbine would be situated a distance which is less than 110% of the blade tip height of the turbine from the curtilage of another dwelling,

(c) if the blade tip height of the wind turbine would exceed 15 metres,

(d) if the lowest part of the wind turbine blade tip would be less than 5 metres from ground level,

(e) within—

(i) a conservation area,

(ii) the curtilage of a listed building,

(iii) a World Heritage Site,

(iv) a site of special scientific interest,

(v) a site of archaeological interest.

(3) Development is permitted by this class subject to the following conditions—

(a) the developer must before beginning the development apply to the planning authority for a determination as to whether the prior approval of the authority will be required in respect of the siting, design, size and external appearance of the proposed wind turbine,

(b)the application is to be accompanied by—

(i) a written description of the proposed development, including details of the siting, design, size and external appearance of the proposed wind turbine, and

(ii) a plan indicating the site,

(c)the development is not to be commenced before the occurrence of one of the following—

(I)the receipt by the applicant from the planning authority of a written notice of their determination that prior approval in respect of the siting, design, size and external appearance of the proposed wind turbine is not required,

(ii) the expiry of a period of 28 days following the date on which the application was received by the planning authority without the planning authority giving notice of their determination that such approval is required, or

(iii) where the planning authority gives the applicant notice within a period of 28 days following the date of receiving the application of their determination that such prior approval is required, the giving of such approval,

(d)the development must, except to the extent that the planning authority otherwise agree in writing, be carried out—

(i) to the extent to which prior approval is required, in accordance with the details approved,

(ii) to the extent to which prior approval is not required, in accordance with the details submitted with the application,

(e)the development is to be carried out within a period of three years from the date on which all approvals required in accordance with this paragraph have been given,

(f) the wind turbine must comply with MCS Planning Standards for wind turbines or equivalent standards,

(g) the wind turbine (including the blades) must be constructed and maintained in a uniform external finish and colour and be free from external rust, staining or discolouration,

(h) if the wind turbine is no longer needed for, or capable of, the generation of electricity it must be removed as soon as reasonably practicable.

Wind Turbines on Detached Dwellinghouses (Class 6HC)

6.22 Class 6HC allows the installation, alteration or replacement of a wind turbine on a detached dwellinghouse.

6.23 The PDR apply solely to detached dwellinghouses and therefore do not allow installation, alteration or replacement on terraced or semi-detached houses or on buildings containing flats. The intention is to minimise the potential for nuisance to be caused to neighbours through shadow flicker, noise, or vibration and to minimise potential for damage to other persons’ property in the event the turbine became detached from the building.

6.24 The following limitations also apply:

• There can be no more than one turbine on the same dwellinghouse (a free-standing turbine within the curtilage would not count towards this restriction and vice versa),
• No part of the turbine may protrude more than 3m above the highest part of the roof, excluding the chimney, of the dwellinghouse,
• No part of the turbine may be less than 5m from ground level,
• The swept area of the turbine must not be more than 4 square metres
• No part of the turbine may be less than 5m from the boundary of the curtilage of the dwellinghouse,
• Development is not permitted in a conservation area, a World Heritage Site, a site of special scientific interest, on a listed building or within the curtilage of a listed building.
• The turbine must comply with MCS planning standards for wind turbines or equivalent standards.

6.26 The turbine must be constructed and maintained in a uniform colour, including the blades, and must be kept rust free and free from advertisements, external staining or other discolouration.

6.27 Where the wind turbine equipment is no longer needed, or the equipment becomes incapable of being used, for example through breakdown that cannot be or is not repaired, the condition requires that it must be removed as soon as reasonably practicable.

Legislation

Class 6HC

(1) The installation, alteration or replacement of a wind turbine on a detached dwellinghouse.

(2) Development is not permitted by this class—

(a) if it would result in the presence on the same dwellinghouse of more than one wind turbine,

(b) if any part of the wind turbine would protrude more than 3 metres above the highest part of the roof (excluding any chimney) of the dwellinghouse,

(c) if any part of the wind turbine would be less than 5 metres from ground level,

(d) if the swept area of the turbine would be more than 4 square metres,

(e) if any part of the wind turbine would be less than 5 metres from the boundary of the curtilage of the dwellinghouse,

(f) in the case of a dwellinghouse—

(i) in a conservation area,

(ii) in a World Heritage Site,

(iii) in a site of special scientific interest,

(iv) which is a listed building or is in the curtilage of a listed building.

(3) Development is permitted by this class subject to the following conditions—

(a) the wind turbine must comply with MCS Planning Standards for wind turbines or equivalent standards,

(b) the wind turbine must be constructed and maintained in a uniform external finish and colour and be free from advertisements, external rust, staining or discolouration, and

(c) if the wind turbine is no longer needed for, or capable of, generating electricity it must be removed as soon as reasonably practicable.

Solar Panels on Dwellings (Class 6HA)

6.28 Class 6HA : The installation, alteration or replacement of solar photovoltaic or solar thermal equipment (often collectively referred to as solar panels) on a dwelling.

6.29 The following restrictions apply;

• No part of the solar panel equipment may protrude more than 1m from the surface of the wall, roof plane, roof ridge or chimney.
• Development is not permitted on a listed building or within the curtilage of a listed building.
• In a conservation area, development is permitted provided the solar panels and equipment are mounted on a rear elevation or a side elevation if that side elevation does not front a road.

Condition

6.30 Where the solar panel equipment is no longer needed or is incapable of generating heat or electricity, as the case may be, it must be removed as soon as is reasonably practical.

Legislation

Class 6HA

(1) The installation, alteration or replacement of solar PV or solar thermal equipment on a dwelling.

(2) Development is not permitted by this class if—

(a) it would protrude more than 1 metre from the outer surface of an external wall, roof plane, roof ridge or chimney of the dwelling,

(b) the dwelling is situated in a conservation area and the solar PV or solar thermal equipment would be located on—

(i) the principal elevation, or

(ii) a side elevation where that elevation fronts a road,

(c) the dwelling is —

(i) a listed building or is within the curtilage of a listed building,

(ii) within a World Heritage Site.

(3) Development is permitted by this class subject to the condition that solar PV or solar thermal equipment which is no longer needed for, or capable of, the generation of electricity or the production of heat, as the case may be, must be removed as soon as reasonably practicable.

Solar panels mounted on outbuildings within the curtilage of a dwelling (Class 6HB)

6.31 Class 6HB allows the installation, alteration or replacement of solar panels on a building within the curtilage of a dwelling. This covers both solar photovoltaic and solar thermal equipment.

6.32 The following restrictions apply;

• Development is not permitted if the solar panels/equipment would protrude more than 500mm (50cm) from the external wall, roof plane, roof ridge or chimney of the building they are affixed to.
• The building the solar equipment is affixed to must not be in the front curtilage of the dwelling.
• PDR do not apply to listed buildings or buildings within the curtilage of a listed building or within a World Heritage Site.

Conditions

6.33 Development is permitted by this class subject to the condition that if the equipment is no longer needed or is incapable of generating heat or electricity (as the case may be) it must be removed as soon as is reasonably practicable.

6.34 There are no additional restrictions on placement of solar panels on outbuildings in conservation areas other than the general restriction that the building cannot be within the front curtilage of the dwelling. Nor are there any restrictions on the number of outbuildings to which such equipment can be attached, although it is important to remember that the buildings themselves must have planning permission, either under Class 3A or as a decision on a planning application.

Legislation

Class 6HB

(1) The installation, alteration or replacement of solar PV or solar thermal equipment on a building situated within the curtilage of a dwelling.

(2) Development is not permitted by this class if—

(a) it would protrude more than 500 millimetres from the outer surface of an external wall, roof plane, roof ridge or chimney of the building,

(b) the building is situated in the front curtilage of the dwelling,

(c) the building is—

(i) a listed building or within the curtilage of a listed building,

(ii) within a World Heritage Site,

(d) it would be development described in Class 6HA(1).

(3) Development is permitted by this class subject to the condition that solar PV or solar thermal equipment which is no longer needed for, or capable of, the generation of electricity or the production of heat, as the case may be, must be removed as soon as reasonably practicable.

(4) In this class “front curtilage” means that part of the curtilage of the dwelling forward of the principal elevation of the dwelling.

Flues for Biomass Heating System (Class 6C)

6.35 PDR allow the installation, alteration or replacement of a flue, forming part of a biomass heating system, on a dwellinghouse or building containing a flat.

6.36 If the flue exceeds any of the following limitations, then an application for planning permission is required.

6.37 A planning permission is needed for flues for dwellinghouses or flats within an Air Quality Management Area. Air Quality Management Area has the meaning given in section 83(1) of the Environment Act 1995.

6.38 Planning permission is required if the flue is to be attached to the principal elevation of a dwellinghouse or flat within a conservation area or World Heritage Site. The identification of the principal elevation is discussed in section 3.

Legislation

Class 6C.-

(1) The installation, alteration or replacement of a flue, forming part of a biomass heating system, on a dwellinghouse or building containing a flat.

(2) Development is not permitted by this class if-

(a) the height of the flue would protrude more than one metre above the highest part of the roof (excluding any chimney) on which the flue is fixed;

(b) in the case of land within a conservation area or a World Heritage Site, the flue would be installed on the principal elevation of the dwellinghouse or building containing a flat; or

(c) the flue would be within an Air Quality Management Area.

Flues for Combined Heat and Power System (Class 6F)

6.39 Flues for Combined Heat and Power System PDR allow the installation, alteration or replacement of a flue for combined heat and power system, on a dwellinghouse or building containing a flat.

6.40 If the flue exceeds any of the following limitations, then an application for planning permission is required.

6.41 A planning permission is needed for flues for dwellinghouses or flats within an Air Quality Management Area. Air Quality Management Area has the meaning given in section 83(1) of the Environment Act 1995.

6.42 Planning permission is required if the flue is to be attached to the principal elevation of a dwellinghouse or flat within a conservation area or World Heritage Site. The identification of the principal elevation is discussed in section 3.

Legislation

Class 6F.-

(1) The installation, alteration or replacement of a flue, forming part of a combined heat and power system, on a dwellinghouse or building containing a flat.

(2) Development is not permitted by this class if-

(a) the height of the flue would protrude more than 1 metre above the highest part of the roof (excluding any chimney) on which the flue is fixed;

(b) in the case of land within a conservation area or World Heritage Site, the flue would be installed on the principal elevation of the dwellinghouse, or building containing a flat; or

(c) in the case of a combined heat and power system fuelled by biomass sources, the flue would be within an Air Quality Management Area.