Green oak is freshly felled oak that has not been seasoned or dried, and therefore still contains a high proportion of moisture. It is softer and easier to cut, shape and join than seasoned timber, and it has traditionally been used for building frames, barns, roof structures and other carpentry.
Medieval and Tudor carpenters generally worked oak green, cutting and assembling timber frames soon after felling and securing joints with oak pegs. As the timber dried in place, it shrank, twisted and developed splits known as shakes or checks, and the frame settled, giving historic timber-framed buildings their characteristic irregular lines. For furniture, oak was usually split or sawn and allowed to dry before use, as green timber would move and crack. Antique oak beams, frames and boards often show the effects of drying in the form of splits, twisting and a silvery weathered surface. In recent decades green oak has seen a revival in new timber-framed houses, extensions, porches and garden buildings. For restorers and those working on historic buildings, understanding how green oak behaves as it dries is essential for sympathetic repair, as is matching old and new timber in species, grain and finish.
