Ethnographic sources confirm that thatching with straw was the main method of protecting rural buildings against precipitation in the lowlands of central Europe. Thatch was made of ‘straight’ rye straw whose stalks – as the name indicates – had not been broken or crumpled in any way during reaping or threshing. The straw had to be long (120-140cm) and of proper flexibility and thickness, which could be attained through appropriate cultivation.
The following were the two principal methods of thatching with straw:
1.Thatch was made from specially bound sheaves of rye straw prepared prior to starting work on the roof. The sheaves usually consisted of two bundles of straw tied together with a thin straw wisp whose stable form resulted from the appropriate twisting of stalks around each other. Each sheaf weighed around 1,5-2 kg and was 100-130cm long. Depending on the method of arrangement on the roof, sheaves could be divided into those:
- with the lower (cut) part of the sheaf pointing downwards
- with the upper (uncut) part of the sheaf pointing downwards
On commencing work on the roof, the sheaves prepared beforehand were fastened to the horizontal laths, each of which was 40cm in length, and were laid end-to-end. Thatching, therefore, involved fastening the consecutive sheaves to separate laths, starting from the lowest part of the roof. As a result every further layer above would overlap with the layer below. Roofs covered by straw sheaves were very stable since they could protect buildings reliably for 30-40 years. This way of making thatch also enabled numerous artistic approaches. For example, thatch could be made entirely smooth, stepped throughout, or with steps solely in the roof corners.
2. In the second method, the 30cm-thick straw was lain out loosely on the roof. Then, using a special perch tied to the lath by means of wicker withies or wire, the straw was pressed on to the roof. Afterwards, another layer of straw was used to cover separate perches, making them invisible until reaching the roof ridge. As a result, this method allowed for making completely smooth thatch.