SCHEDULE 2Permitted development rights
PART 7Non-domestic extensions, alterations etc
Class F – extensions etc of office buildings
Permitted development
F.
The extension or alteration of an office building.
Development not permitted
F.1
Development is not permitted by Class F if—
(a)
the gross floor space of the original building would be exceeded by more than—
(i)
in respect of an original building or a development on—
(aa)
article 2(3) land, or
(bb)
on a site of special scientific interest,
25% or 50 square metres (whichever is the lesser);
(ii)
in any other case, 50% or 100 square metres (whichever is the lesser);
(b)
the height of the building as extended would exceed—
(i)
if within 10 metres of a boundary of the curtilage of the premises, 5 metres; or
(ii)
in all other cases, the height of the building being extended;
(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 alteration would be on article 2(3) land; F1...
(e)
the development would be within the curtilage of a listed building F2; or
F3(f)
the building is in use as an office as permitted by Class JA (retail, takeaway, betting office, pay day loan shop, and launderette uses to offices) of Part 3 of this Schedule.
Conditions
F.2
Development is permitted by Class F subject to the following conditions—
(a)
any office building as extended or altered is only used as part of, or for a purpose incidental to, the use of that office building;
(b)
any extension is, in the case of article 2(3) land, constructed using materials which have a similar external appearance to those used for the building being extended; and
(c)
any alteration is at ground floor level only.
Interpretation of Class F
F.3
For the purposes of Class F, where 2 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.