Masonry crack injection, also referred to as low-pressure injection is needed when there is a fault, crevice, or crack in a concrete or stone wall. Whether caused by an earthquake, accident, or bad foundation, low-pressure injection of grout into walls can be a cost-effective method of repair as opposed to replacing the entire wall. It is a good idea to get cracks sealed and reinforced immediately because the longer you wait to repair the crack, the more the integrity of your structure can dwindle.