Ondol

Ondol or gudeul (구들; [ku.dɯl]) in <a href="/facts/Korea/cj2kDBzc">Korean</a> traditional architecture is <a href="/facts/Underfloor_heating/FBRACoeH">underfloor heating</a> that uses direct <a href="/facts/Heat_transfer/1IV3WbFL">heat transfer</a> from wood smoke to heat the underside of a thick <a href="/facts/Masonry/TlaDzpUp">masonry</a> floor. In modern usage, it refers to any type of underfloor heating, or to a hotel or a sleeping room in Korean (as opposed to Western) style.
The main components of the traditional ondol are an <a href="/facts/Agungi/TeB7fpMj">agungi</a> (아궁이; [a.guŋ.i]), a <a href="/facts/Firebox_(architecture)/0d51kCG4">firebox</a> or <a href="/facts/Stove/KlLJu3dz">stove</a>, accessible from an adjoining room (typically kitchen or master bedroom), a raised <a href="/facts/Masonry/TlaDzpUp">masonry</a> floor underlain by horizontal smoke passages, and a vertical, freestanding <a href="/facts/Chimney/8aQXjVzj">chimney</a> on the opposite exterior wall providing a draft. The heated floor, supported by stone piers or baffles to distribute the smoke, is covered by stone slabs, clay and an impervious layer such as oiled paper.

Ondol open-in-new

Ondol