The Planning (General Permitted Development) Order (Northern Ireland) 2015

PART 35 OFFICE BUILDINGS

Class A
Permitted development	A.	The extension or alteration of an office building.
Development not permitted	A.1	Development is not permitted by Class A if— (a) the floor space of the original building would be exceeded by more than— (i) 25%; or (ii) 50 square metres; whichever is the lesser; (b) the height of the building as extended or altered would exceed— (i) if within 10 metres of a boundary of the curtilage of the premises, 5 metres; (ii) in all other cases, the height of the building being extended or altered; (c) any part of the development, other than an alteration, would be within 5 metres of any boundary of the curtilage of the premises; (d) any part of the development would face onto a road; (e) the development would consist of or include the construction or provision of a veranda, balcony or raised platform; (f) the development would lead to a reduction in the space available for the parking or turning of vehicles; (g) the development would be within the curtilage of a listed building unless listed building consent has previously been granted; or (h) any extension or alteration would be in a conservation area, a World Heritage Site, an area of special scientific interest or a site of archaeological interest.
Conditions	A.2	Development is permitted by Class A subject to the following conditions— (a) any alteration shall be at ground floor level only; (b) any extension shall be constructed using materials which have a similar external appearance to those used for the building being extended; and (c) any office building as extended or altered shall only be used as part of, or for a purpose incidental to the use of that office building.
Interpretation of Class A	A.3	For the purposes of Class A— (a) where two or more original buildings are within the same curtilage and are used for the same undertaking they are to be treated as a single original building in making any measurement; (b) “office building” means a building used for any purpose within Class B1 of the Schedule to the Use Classes Order; (c) “raised platform” means a platform with a height greater than 0.3 metres above ground level.
Class B
Permitted development	B.	Development consisting of— (a) the provision of a hard surface within the curtilage of an office building to be used for the purposes of the office concerned; or (b) the replacement in whole or in part of such a surface.
Development not permitted	B.1	Development is not permitted by Class B if— (a) the cumulative area of ground covered by a hard surface within the curtilage of the site (other than hard surfaces already existing on 19th September 2012) would exceed 50 square metres; (b) the development would be within the curtilage of a listed building unless listed building consent has previously been granted.
Conditions	B.2	Development is permitted by Class B subject to the following conditions— (a) where there is a risk of groundwater contamination the hard surface shall not be made of porous materials; (b) in all other cases, either— (i) the hard surface shall be made of porous materials; or (ii) provision shall be made to direct run-off water from the hard surface to a permeable or porous area or surface within the curtilage of that office building.
Interpretation of Class B	B.3	For the purposes of Class B “office building” means a building used for any purpose within Class B1 of the Schedule to the Use Classes Order.