As the foundation was dug, the walls were constructed using stone, brick, or wood. In some cases, the basement walls were simply dug into the side of a hill or slope. Once the walls were completed, the floor of the basement was dug out, and any necessary drainage systems were installed. Finally, the basement was covered with a roof and the floor was finished with wood, stone, or tile.
In the 20th century, the introduction of heavy machinery made digging basements much easier and faster. Power shovels, backhoes, and bulldozers could quickly dig large holes in the ground, making it possible to construct basements in just a few days. Today, most basements are dug using heavy machinery, but in some cases, they are still hand-dug.