Formwork is a design that allows the concrete to fill the entire volume of the excavation and to give the foundation the desired shape. For the construction of the structure wood of any kind is used, but most often it is pine or spruce.

When choosing the material, it is necessary to take into account the thickness of the board for the formwork. Along with the length it is the main of the parameters affecting the quality of the fill. Before making the formwork, the boards are knocked down into shields, which restrict the shape of the future foundation.

In the process of pouring a concrete mortar, which has a large mass and a high density index, creates pressure on the walls of the formwork. If the thickness of the wood is insufficient, the structure will collapse.