National Flannel Day

What the day is

National Flannel Day is observed on February 10, in the part of winter when the case for it is strongest.

Origin and background

Flannel is not a pattern and not strictly a material. It is a finishing process. Cloth, traditionally wool and now often cotton, is passed under fine metal brushes that lift and break the ends of the fibers on the surface, raising a soft nap. That nap traps a layer of still air against the skin, and trapped air is what insulates, which is why flannel feels warm at a weight where plain woven cloth does not.

The confusion with plaid is entirely American and entirely commercial. Flannel shirts were sold in checked patterns for so long that the pattern took the name, but a plain black flannel shirt is flannel and a checked cotton poplin shirt is not. The particular check most people picture, in red and black, belongs to a Canadian and American workwear tradition rather than to flannel as such.

The origin is generally traced to Wales, where the woolen industry produced a light napped cloth, and the word appears to derive from a Welsh term for wool. It spread through British industrialization as a practical fabric for working people, then to North American logging and farming, which is where the lumberjack association comes from.

Its 1990s revival through Pacific Northwest music was less a style choice than a climate one: it is what was cheap and warm in a wet region, and it became a signifier afterward.

The nap is also the weak point. Washing at high temperature and heavy tumble drying mat the raised fibers down, which is what turns a soft shirt stiff and pilled.

How to take part

• Wear it, plain or checked. Both are equally flannel.
• Wash cool and dry low to protect the nap.
• Compare wool flannel with cotton. They behave very differently when damp.
• Check the weight before buying, since flannel ranges from shirting to blanket.
• Look up why it is called flannel, which points back to Wales rather than Oregon.