Wooden Planks are a Building Material that can be found in Apocalypse Rising. To use these effectively you have to pick it up, deploy them, and then there you go. You must have an entrencher to move wooden planks. These also take some inventory space so plan accordingly.
Building Materials commonly spawn in areas such as warehouses and the Industrial side of Kin. They are used to fortify buildings. You can create a lot of things such as stairs, railings, repairing walls, etc, and in my opinion is the most versatile of all building materials.