In rehabilitation work, and occasionally in relatively new properties, brickwork is sometimes found to be in poor condition: the mortar is powdery and easily rubbed away or eroding so that the joints have become appreciably recessed. The builder has to decide whether there is any loss of strength in the wall and, if there is, if repointing will adequately restore that strength and make the joints sufficiently durable. It is important to ensure that the mortar is not stronger than the brick. This Good Repair Guide gives advice to builders and householders on choosing the right mortar mix and how to repoint.