R.1 Development is not permitted by Class R if—
(a)the building was not used solely for an agricultural use as part of an established agricultural unit—
(i)on 3rd July 2012;
(ii)in the case of a building which was in use before that date but was not in use on that date, when it was last in use, or
(iii)in the case of a building which was brought into use after 3rd July 2012, for a period of at least 10 years before the date development under Class R begins;
(b)the cumulative floor space of buildings which have changed use under Class R within an established agricultural unit exceeds 500 square metres;
(c)the site is, or forms part of, a military explosives storage area;
(d)the site is, or forms part of, a safety hazard area; or
(e)the building is a listed building or a scheduled monument.