A lean-to is a type of simple structure originally added to an existing building with the rafters "leaning" against another wall. Free-standing structures open on one or more sides (colloquially referred to as lean-tos in spite of being unattached to anything) are generally used as shelters.

Lean-to, French: Appentis, built against the walls of Meaux Cathedral
A typical free-standing Adirondack-style lean-to shelter

A lean-to addition is an appendix to an existing structure constructed to fulfill a new need. Sometimes, it covers an external staircase, as in a 15th century addition against one of the walls of the large chapter room of the cathedral of Meaux. Other uses include protecting entrances, or establishing covered markets outside existing buildings.[1]

Examples

Lean-to made with car and tent

A lean-to is originally defined as a structure in which the rafters lean against another building or wall, also referred to in prior times as a penthouse.[2] These structures characteristically have shed roofs, also referred to as "skillions", or “outshots” and “catslides” when the shed’s roof is a direct extension of a larger structure’s.

A lean-to shelter is a simplified free-standing version of a wilderness hut with three solid walls and a single- or, in the case of an Adirondack lean-to, offset-pitched gable roof. The open side is commonly oriented away from the prevailing weather. Often it is made of rough logs or unfinished wood and used for camping.

A laavu in the Pukala recreational forest

This style of lean-to is popular in Finland and Scandinavia, and known as a laavu in Finnish, gapskjul or slogbod in Swedish, and gapahuk in Norwegian.

References

  • Media related to lean-to at Wikimedia Commons