In this instance the thatch is fixed directly to the roof frame, either to a new structure or after all existing thatch has been removed. In the past, fixing was done mostly by tying to the roof rafters (or sometimes the battens) with various materials, for instance twisted hazel rod, tarred twine etc. Tying is now rarely used as a fixing for a main coat (although it is still used to fix base coats) and the most common fixing method these days is by crook and sway. A crook is a large spiked hook driven into each rafter to hold down a horizontal rod (sway) made of either wood or more commonly, steel. The sway clamps each course of material to the roof and each successive course covers the fixings of each previous course. The first course is laid at the eaves and the work then continues up the roof with the ridge covering the fixings of the final course.