The site was built on farm land acquired by compulsory purchase order. Over of land from up to seven farms was used to accommodate the factory. The land included the Grade B listed Dargavel House and its grounds once owned by the entrepreneur Edward Steinkopff; the house still survives within the site boundary, as well as several former farm houses and public roads that were absorbed into the ROF site. The southern end of the site included land occupied by the former National Filling Factory (a WW1 munitions factory).