The Town and Country Planning (General Permitted Development) Order 1995

[F1Class BE+W

Permitted developmentE+W

B.  The extension or alteration by or on behalf of the Crown of an operational Crown building.

Development not permittedE+W

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

(a)the building as extended or altered is to be used for purposes other than those of—

(i)the Crown; or

(ii)the provision of employee facilities;

(b)the height of the building as extended or altered would exceed the height of the original building;

(c)the cubic content of the original building would be exceeded by more than—

(i)10%, in respect of development on any article 1(5) land; or

(ii)25%, in any other case;

(d)the floor space of the original building would be exceeded by more than—

(i)500 square metres in respect of development on any article 1(5) land; or

(ii)1,000 square metres in any other case;

(e)the external appearance of the original building would be materially affected;

(f)any part of the building as extended or altered would be within 5 metres of any boundary of the curtilage of the original building; or

(g)the development would lead to a reduction in the space available for the parking or turning of vehicles.

Interpretation of Class BE+W

B.2  For the purposes of Class B—

(a)the erection of any additional building within the curtilage of another building (whether by virtue of Class B or otherwise) and used in connection with it is to be treated as the extension of that building, and the additional building is not to be treated as an original building;

(b)where two or more original buildings are within the same curtilage and are used for the same operational purposes, they are to be treated as a single original building in making any measurement;

(c)“employee facilities”means social, care or recreational facilities provided for employees or servants of the Crown, including crèche facilities provided for the children of such employees or servants.]