Löyly

Löyly is the steam and humidity produced in a sauna, created when water is poured onto hot stones. It is a defining feature of the Finnish sauna tradition and shapes both the temperature and the overall atmosphere of the room.

The term löyly comes from Finnish and refers to the steam itself as well as the life-like energy or mood created by the rising heat. In everyday use, it is the word people use to describe the enveloping warmth and the feel of the sauna environment.

Production and effect: In a traditional wood- or electric-stove sauna, stones are heated to a high temperature. Pouring water on the stones instantly generates steam; more water produces stronger löyly and greater humidity. The resulting heat is perceived differently as air moves and the steam rises, so occupants may experience a range of sensations from comforting warmth to a more intense, immersive heat.

Cultural context: Löyly is central to sauna etiquette in Finland. Saunas are typically designed to manage and modulate steam, and people may intensify löyly with additional pours or, in some traditions, the use of birch twigs (vihta) for a light massage-like effect. Sauna sessions commonly alternate between heating, löyly, cooling, and rest, reflecting a balance of warmth, social interaction, and relaxation.