Apost in ground construction, also calledearthfast^[1] orhole-set posts, is a type of construction in which vertical, roof-bearing timbers, calledposts, are in direct contact with the ground. They may be placed into excavatedpostholes,^[2] driven into the ground, or on sills which are set on the ground without a foundation. Earthfast construction is common from theNeolithic period to the present and is used worldwide. Post-in-the-ground construction is sometimes called an "impermanent" form, used for houses which are expected to last a decade or two before a better quality structure can be built.^[3]

Post in ground construction can also include sill on grade,wood-lined cellars, andpit houses. Most pre-historic and medieval wooden dwellings worldwide were built post in ground.

This type of construction is often believed^{[by whom?]} to be an intermediate form between apalisade construction and a stave construction. Because thepostholes are easily detected in archaeological surveys, they can be distinguished from the other two.

Post in ground was one of the timber construction methods used for French colonial structures inNew France; it was calledpoteaux-en-terre.

The Japanese also used a type of earthfast construction until the eighteenth century, which they call Hottate-bashira (literally "embedded pillars").^[4]

TheDogon people in Africa use post in ground construction for theirtoguna, community gathering places typically located in the center of villages for official and informal meetings.

In the historical region ofNew France in North America,poteaux-en-terre was a historic style of earthfasttimber framing. This method is similar topoteaux-sur-sol, but theboulin (hewn posts) are planted in the ground rather than landing on asill plate. The spaces between the boulin are filled withbousillage (reinforced mud) orpierrotage (stones and mud). Surviving examples of both types of structures can be found atSte. Genevieve, Missouri.

•  
  Drawing of poteaux-en-terre in the Beauvais House inSte Genevieve, Missouri
•  
  A cross section of a poteaux-en-terre house.
•  
  A model of the Beauvais-Amoureux House, showing poteaux-en-terre construction.
•  
  Poteaux-en-Terre-Cellar of the Maison Beauvais-Amoureux.
•  
  First Courthouse, St. Louis, Missouri; from a c. 1915 postcard.

• French colonization of the Americas
• Old Spanish Fort (Pascagoula, Mississippi). The La Pointe-Krebs House.
• Pit-house
• Post church
• Ste. Genevieve, Missouri
• Stilt house

• EARTHFAST ARCHITECTURE IN EARLY MAINE
• Earthfast Architecture at the Association for the Preservation of Virginia Antiquities