Class K: Stand-alone solar equipment on non-domestic premises

Class K allows one stand-alone solar installation within the curtilage of a non-domestic building, subject to height, boundary, panel-area and protected-site limits.

Prior approval is required only for the specified article 2(3) land case where the equipment would be nearer to a highway than the nearest part of the building.

Size and siting

The installation must ordinarily be no higher than four metres and no part may be within five metres of the curtilage boundary. Panels cannot exceed nine square metres in total and the array’s largest dimension cannot exceed three metres. Where it sits closer to a highway than the building on article 2(3) land, the height limit is two metres and the prior approval condition applies.

Scheduled monuments and the curtilage of listed buildings are excluded, and redundant equipment must be removed. Building-mounted solar equipment is under Class J. Read Part 14, Class K.

Legislation

Class K – installation or alteration etc of stand-alone solar equipment on non-domestic premises

Permitted development

K. The installation, alteration or replacement of stand-alone solar for microgeneration within the curtilage of a building other than a dwellinghouse or a block of flats.

Development not permitted

K.1 Development is not permitted by Class K if—

(a) in the case of the installation of stand-alone solar, the development would result in the presence within the curtilage of more than 1 stand-alone solar;

(b) any part of the stand-alone solar—
(i) would exceed 4 metres in height or, in the case of stand-alone solar installed on article 2(3) land so that it is nearer to any highway which bounds the curtilage than the part of the building which is nearest to that highway, 2 metres in height;
(iii) would be installed within 5 metres of the boundary of the curtilage;
(iv) would be installed within the curtilage of a listed building; or
(v) would be installed on a site designated as a scheduled monument; or

(c) the surface area of the solar panels forming part of the stand-alone solar would exceed 9 square metres or any dimension of its array (including any housing) would exceed 3 metres.

Conditions

K.2 Development is permitted by Class K subject to the following conditions—

(a) the stand-alone solar must, so far as practicable, be sited so as to minimise its effect on the amenity of the area;

(aa) in the case of stand-alone solar installed on article 2(3) land nearer to any highway which bounds the curtilage than the part of the building which is nearest to that highway, before beginning development the developer must apply to the local planning authority for a determination as to whether the prior approval of the local planning authority will be required with respect to the impact of the appearance of the stand-alone solar on that land;

(ab) in relation to an application under sub-paragraph (aa), paragraphs J.4(3) to J.4(12) of this Part apply as if “Class K” substitutes the reference to “Class J” in paragraph J.4(4); and

(b) the stand-alone solar is removed as soon as reasonably practicable when no longer needed.

[section copied from Class J as referred to in sub-paragraph (ab)]

(3) The application must be accompanied by—

(a) a written description of the proposed development;
(b) a plan indicating the site and showing the proposed development;
(c) the developer’s contact address; and
(d) the developer’s email address if the developer is content to receive communications electronically;

together with any fee required to be paid.

(4) The local planning authority may refuse an application where, in the opinion of the authority—

(a) the proposed development does not comply with, or
(b) the developer has provided insufficient information to enable the authority to establish whether the proposed development complies with,

any conditions, limitations or restrictions specified in Class K applicable to the development in question.

(5) Sub-paragraphs (6) and (8) do not apply where a local planning authority refuses an application under sub-paragraph (4) and for the purposes of section 78 (appeals) of the Act such a refusal is to be treated as a refusal of an application for approval.

(6) The local planning authority must give notice of the proposed development—

(a) by site display in at least one place on or near the land to which the application relates for not less than 21 days of a notice which—
(i) describes the proposed development;
(ii) provides the address of the proposed development;
(iii) specifies the date by which representations are to be received by the local planning authority; or

(b) by serving a notice in that form on any adjoining owner or occupier.

(7) The local planning authority may require the developer to submit such information as the authority may reasonably require in order to determine the application.

(8) The local planning authority must, when determining an application—

(a) take into account any representations made to them as a result of any notice given under sub-paragraph (6); and
(b) have regard to the National Planning Policy Framework, so far as relevant to the subject matter of the prior approval, as if the application were a planning application.

(9) The development must not begin before the occurrence of one of the following—

(a) the receipt by the applicant from the local planning authority of a written notice of their determination that such prior approval is not required;
(b) the receipt by the applicant from the local planning authority of a written notice giving their prior approval; or
(c) the expiry of 56 days following the date on which the application under sub-paragraph (3) was received by the local planning authority without the authority notifying the applicant as to whether prior approval is given or refused.

(10) The development must be carried out—

(a) where prior approval is required, in accordance with the details approved by the local planning authority;
(b) where prior approval is not required, or where sub-paragraph (9)(c) applies, in accordance with the details provided in the application referred to in sub-paragraph (3),
unless the local planning authority and the developer agree otherwise in writing.

(11) The local planning authority may grant prior approval unconditionally or subject to conditions reasonably related to the subject matter of the prior approval.

(12) When computing the number of days in paragraph (6)(a), any day which is a public holiday must be disregarded.

Explore GPDO Part 14

Page updated: 24th September 2026