A mortar wall's joints will fracture if it is not built on a solid base. Excavate a trench that is 6 inches broader than your wall. It must be at least 12 inches deep, or deeper than the frost line, for a 3-foot-high wall. At least 8 inches of concrete should be poured into the trench's bottom. The mortar will help distribute weight across a larger surface area and so reduce the chance of one course of bricks or blocks being more vulnerable than others. Mortar is a mixture of water and sand or cement. As the word "mortar" implies, this material is used to bind together the elements of a masonry wall. Most often, mortar is used to connect the courses of brick or block. But it can also be used to attach lintels, headers, or flashings. The type of mortar you use will determine how much work is involved in attaching objects to the wall. There are two types of mortars: dry and wet. Dry mortars are made from powders that are mixed with water to form a paste. These pastes are then applied to the joint between the masonry units. The powder helps the paste adhere to the stones when they are pressed together. After the first coat has dried, another coat can be applied for a smoother finish. Wet mortars are made by mixing cement with water and other additives such as gravel or sand. This mix is then sprayed onto the stone or blocked masonry unit.