Many medieval rooms use stone vaulting supported by columns in the centre of the space, as used for other more utilitarian large rooms in monasteries with a generous budget. Others have much higher roofs. The shape of the room is usually designed to allow good audibility for speakers from all parts of the room. It may be rectangular, tending towards the square, but octagonal and other near-circular plans are an English speciality, with that at Worcester Cathedral probably the earliest. Most, like those at Wells Cathedral, Lichfield Cathedral, Westminster Abbey and Lacock Abbey have a single central column, from which the high roof vaulting spreads. York Minster has a wooden roof and no central column. Many have elaborate benched arcades round the wall, with crocketed frames for the seats. English chapter houses tend to be more elaborate and highly decorated than Continental ones, and the octagonal shape allowed for spectacular displays of stained glass, now mostly lost, though not at York. Except at Westminster Abbey any paintings have been lost, but English designs, with their emphasis on carved arcades and windows, did not leave the large wall spaces found in most Continental chapter houses.