Yealming

Yealming is the ground-level preparation of long straw for thatching. Threshed straw is wetted, drawn out and straightened, and then gathered into tidy, compact layers with both ends level. Each prepared layer is a yealm (also spelled yelm or yealm), which the Thatching Advisory Services glossary describes as a prepared bundle used like a thick roof tile.

Why it is needed

Long straw, unlike combed wheat reed, is not combed after threshing. The stalks keep their ears and are mixed in direction, length and alignment. Without yealming, the straw would be too loose and irregular to lay evenly. Yealming produces a manageable unit with a consistent thickness, so each course can be fixed and shaped neatly.

Process outline

1. Wet the threshed straw thoroughly so it becomes supple and easier to handle.
2. Draw the straw out by hand, removing short material and debris and laying the stalks parallel.
3. Build up a tight, compact layer with both ends level.
4. Gather the finished yealm and carry it up to the roof, where it is laid and fixed with hazel spars.

Building Conservation describes the aim as straightening and tidying the straw into a tight, compact layer that is level at both ends, which makes it manageable on the roof.

Appearance

Because long straw is laid with heads and butts in mixed directions and the surface is not dressed with a legget, long straw roofs have a softer, shaggier look than reed roofs. They are typically fixed with hazel spars and finished with liggers along the eaves, gables and ridge.

Regional use

Long straw was once used across the main corn-growing areas of England from Dorset northwards. Today it is found mainly in East Anglia, with examples elsewhere, and is a recognised regional tradition that heritage authorities often wish to preserve on listed buildings.