After straw and reed, spars are the most important component in English thatched roofs. In essence, they are large ‘staples’ which are used to secure the layers of reed or straw to the roof.
Spars are usually made from hazel, which grows natively in England and is known for it’s use in withy fencing, basket making, wattle walls and also the frames of coracle boats. Hazel is managed as a coppice crop, with harvesting on a roughly 7 year cycle.
Firstly, long, straight sticks of hazel are taken from the copse. These will then be sawn down, to usually just above 2 feet long. At this point the pieces of hazel are known as ‘gads’. These gads will be split along the grain using a specialist bill hook, a number of times depending on the radius of the gad, to form pieces with a close to triangular cross section. Both ends are then sharpened to a point with 3 quick slices of the hook.
The finished spars are usually collected into packs of 250 and tied with bale twine for delivery to thatchers. Careful storage is important, as exposure to frost, sun or rain can sometimes render the spars useless.
Once on the roof, the master thatcher will twist each spar to form a peg, which will be pushed in to the layer of straw or reed as a permanent fixing. Almost all of the spars on the roof will ideally be orientated ‘slightly upward’ so that rain falling on the roof can’t follow the spar’s path into the layers of thatch.
As sometimes many thousands of spars will be used on a Wimborne thatched roof, the few professional spar makers in Dorset are kept very busy.