Permitted development right

Development within the curtilage of a dwellinghouse

Field	Value
CURIE	permitted-development-right:I1-1981-A1
Prefix	permitted-development-right	Facts
Reference	I1-1981-A1	Facts
Name	Development within the curtilage of a dwellinghouse	Facts
Dataset	Permitted development right
Organisation	Ministry of Housing, Communities & Local Government
Start date	1981-04-01
End date
Entry date	2026-01-15	Facts
Typology	category
Notes	A1 suffix indicates that the legislation referred to is an amendment (A) and that it is the first Amendment in that year (1).	Facts
Description	The enlargement improvement or other alteration of a dwellinghouse so long as: (a) the cubic content of the original dwellinghouse (as ascertained by external measurement) is not exceeded by more than (i) in the case of a terrace house, 50 cubic metres or one-tenth, whichever is the greater; or (ii) in any other case, 70 cubic metres or fifteen per cent, whichever is the greater, subject (in either case) to a maximum of 115 cubic metres; (b) the height of the building as so enlarged altered or improved does not exceed the height of the highest part of the roof of the original dwellinghouse; (c) no part of the building as so enlarged altered or improved projects beyond the forewardmost part of any wall of the original dwellinghouse which fronts on a highway; (d) no part of the building (as so enlarged, improved or altered) which lies within a distance of two metres from any boundary of the curtilage of the dwellinghouse has, as a result of the development, a height exceeding four metres; (e) the area of ground covered by buildings within the curtilage (other than the original dwellinghouse) does not thereby exceed fifty per cent of the total area of the curtilage excluding the ground area of the original dwellinghouse: Provided that:- (a) the erection of a garage or coachhouse within the curtilage of the dwellinghouse shall be treated as the enlargement of the dwellinghouse for all purposes of this permission (including the calculation of cubic content) if any part of that building lies within a distance of five metres from any part of the dwellinghouse; (b) the erection of a stable or loose-box anywhere within the curtilage of the dwellinghouse shall be treated as the elargement of the dwellinghouse for all purposes of this permission (including the calculation of cubic content); (c) for the purposes of this permission the extent to which the cubic content of the original dwellinghouse is exceeded shall be ascertained by deducting the amount of the cubic content of the original dwellinghouse from the amount of the cubic content of the dwellinghouse as enlarged, improved or altered (whether such enlargement, improvement or alteration was carried out in pursuance of this permission or otherwise); (d) where any part of the dwellinghouse will, as a result of the development, lie within a distance of five metres from an existing garage or caochhouse, that building shall (for the purpose of calculation of cubic content) be treated as forming part of the dwellinghouse as enlarged, improved or altered; and (e)the limitation contained in subparagraph (d) above shall not apply to the development consisting of:- (i) the insertion of a window (including a dormer window) into a wall or the roof of the original dwellinghouse, the alteration or enlargement of an existing window; or (ii) any other alterations to any part of the roof of the original dwellinghouse	Facts
Documentation url	https://www.legislation.gov.uk/uksi/1981/245/pdfs/uksi_19810245_en.pdf	Facts
Permitted development right part	I	Facts
Permitted development right class	1	Facts

Contents

{
        "curie": "permitted-development-right:I1-1981-A1",
        "prefix": "permitted-development-right",
        "reference": "I1-1981-A1",
        "name": "Development within the curtilage of a dwellinghouse",
        "dataset": "permitted-development-right",
        "organisation-entity": "government-organisation:D1342",
        "start-date": "1981-04-01",
        "end-date": "",
        "entry-date": "2026-01-15",
        "typology": "category",
        "geometry": "",
        "point": "",
        "entity": 11500212,
        "quality": "some",
        "notes": "A1 suffix indicates that the legislation referred to is an amendment (A) and that it is the first Amendment in that year (1).",
        "description": "The enlargement improvement or other alteration of a dwellinghouse so long as: (a) the cubic content of the original dwellinghouse (as ascertained by external measurement) is not exceeded by more than (i) in the case of a terrace house, 50 cubic metres or one-tenth, whichever is the greater; or (ii) in any other case, 70 cubic metres or fifteen per cent, whichever is the greater, subject (in either case) to a maximum of 115 cubic metres; (b) the height of the building as so enlarged altered or improved does not exceed the height of the highest part of the roof of the original dwellinghouse; (c) no part of the building as so enlarged altered or improved projects beyond the forewardmost part of any wall of the original dwellinghouse which fronts on a highway; (d) no part of the building (as so enlarged, improved or altered) which lies within a distance of two metres from any boundary of the curtilage of the dwellinghouse has, as a result of the development, a height exceeding four metres; (e) the area of ground covered by buildings within the curtilage (other than the original dwellinghouse) does not thereby exceed fifty per cent of the total area of the curtilage excluding the ground area of the original dwellinghouse: Provided that:- (a) the erection of a garage or coachhouse within the curtilage of the dwellinghouse shall be treated as the enlargement of the dwellinghouse for all purposes of this permission (including the calculation of cubic content) if any part of that building lies within a distance of five metres from any part of the dwellinghouse; (b) the erection of a stable or loose-box anywhere within the curtilage of the dwellinghouse shall be treated as the elargement of the dwellinghouse for all purposes of this permission (including the calculation of cubic content); (c) for the purposes of this permission the extent to which the cubic content of the original dwellinghouse is exceeded shall be ascertained by deducting the amount of the cubic content of the original dwellinghouse from the amount of the cubic content of the dwellinghouse as enlarged, improved or altered (whether such enlargement, improvement or alteration was carried out in pursuance of this permission or otherwise); (d) where any part of the dwellinghouse will, as a result of the development, lie within a distance of five metres from an existing garage or caochhouse, that building shall (for the purpose of calculation of cubic content) be treated as forming part of the dwellinghouse as enlarged, improved or altered; and (e)the limitation contained in subparagraph (d) above shall not apply to the development consisting of:- (i) the insertion of a window (including a dormer window) into a wall or the roof of the original dwellinghouse, the alteration or enlargement of an existing window; or (ii) any other alterations to any part of the roof of the original dwellinghouse",
        "documentation-url": "https://www.legislation.gov.uk/uksi/1981/245/pdfs/uksi_19810245_en.pdf",
        "permitted-development-right-part": "I",
        "permitted-development-right-class": "1"
    }

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