1) A horizontal timber, supported by a wall or by posts, which in turn supported the timbering of the roof.
1420 thay awarde and deme that William Selby hafe abouen the same walle space to ryst hys walleplat apon, York
1537 a payr of forks ... vii Sparrs ... a Wallplatt, Bridlington
1538 the inside of the gatehouse wantes in timber for wall playtes, bandes, entre cases, gestes, window selys, Knaresborough Castle
1615 a rough wall to the wall plates and thatch and timber accordingly, Bowland
1642 they will sowe downe theire thatch ... first close to the very wallplates, Elmswell.