The Penrhyn Quarry office is a single-storey building in Italianate style, dating from around 1860 when the quarry (nprn 40564) was undergoing expansion; in recent years the office building has been considerably extended. The walls are coursed and dressed rubblestone, with finely jointed voussoirs to door and window surrounds, under a mainly hipped slate roof.
B.A.Malaws, RCAHMW, 15 May 2008.