The shape of roofs differs greatly from region to region. The main factors which influence the shape of roofs are the climate and the materials available for roof structure and the outer covering. Roofing Preston is a city and the administrative centre of Lancashire, England. On the north bank of the River Ribble, it is an urban settlement and unparished area that together with surrounding rural civil parishes forms the City of Preston local government district of Lancashire. The district obtained city status in 2002, becoming England’s 50th city in the 50th year of Queen Elizabeth II’s reign.