Details dendrochronological studies on oak timbers from the Bishops' House, Sheffield. Curves were obtained from 1350 to 1590, and an almost perfect match was achieved with the Welsh carve' (based on materials from Worcestershire and Wales). The correspondence in growth pattern between timbers used the Sheffield and in the west Midlands/Wales is discussed, in relation to the question of the provenance of the building materials. Growth patterns are also similar in S. Germany and in N. Ireland. -- AATA