Stave church

A stave church is a medieval wooden Christian church building once common in north-western Europe. The name derives from the building's structure of post and lintel construction, a type of timber framing where the load-bearing ore-pine posts are called stafr in Old Norse (stav in modern Norwegian). Two related church building types also named for their structural elements, the post church and palisade church, are often called 'stave churches'.

Originally much more widespread, most of the surviving stave churches are in Norway. The only remaining medieval stave churches outside Norway are: Hedared stave church (c. 1500) in Sweden and the Vang Stave Church which was built in Norway and relocated in 1842 to contemporary Karpacz in the Karkonosze mountains of Poland. One other church, the Anglo-Saxon Greensted Church in England, exhibits many similarities with a stave church but is generally considered a palisade church.

Archaeological excavations have shown that stave churches are descended from palisade constructions and from later churches with earth-bound posts.

Similar palisade constructions are known from buildings from the Viking Age. Logs were split in two halves, set or rammed into the earth (generally called post in ground construction) and given a roof. This proved a simple but very strong form of construction. If set in gravel, the wall could last many decades, even centuries. An archaeological excavation in Lund uncovered the postholes of several such churches.

In post churches, the walls were supported by sills, leaving only the posts earth-bound. Such churches are easy to spot at archaeological sites as they leave very distinct holes where the posts were once placed. Occasionally some of the wood remains, making it possible to date the church more accurately using radiocarbon dating or dendrochronology. Under the Urnes Stave Church, remains of two such churches have been found, with Christian graves discovered beneath the oldest church structure.

A single church of palisade construction has been discovered under the Hemse stave church.

The next design phase resulted from the observation that earthbound posts were susceptible to humidity, causing them to rot away over time. To prevent this, the posts were placed on top of large stones, significantly increasing their lifespans. The Røldal Stave Church is believed to be of this type.

In later churches the posts were set on a raised sill frame resting on stone foundations. This is the stave church in its most mature form.