Over time mortar starts to degenerate and get blown away in the wind, leaving square edges for water to sit on and penetrate the brickwork. This can then lead to all sorts of problems especially when the outside temperature reaches freezing point. When the water penetrates the brickwork it freezes which causes it to expand and creates further damage to the bricks and remaining mortar. The end result is a garden wall that will become unstable and unlikely to sustain a heavy wind.
Houses with old worn mortar are likely to experience damp problems especially older houses which do not have a cavity wall system. This can be avoided by re pointing brickwork with a method that suits your location, for example if you live in an exposed location I would recommend weather struck pointing with a high ratio of cement to sand. By the seaside I would recommend the same style of pointing but with sulphate resisting cement to avoid salt corrosion and so on. Every wall has different requirements so care should be taken when deciding what aggregates to chose for the task in hand.
Pointing can also give a desired decorative effect too. The weather struck finish method mentioned above gives the effect that every brick is in its own little mortar frame which is slanted away from the wall to repell water. This style of finish is time consuming and thus more expensive than traditional bucket handle finish (concave semi circular smooth finish).
If you live in an older or listed building then specialist re-pointing would be required, which can involve using lime putty mixes. This is a time consuming and a specialist task, styles include tuck pointing, normally seen on red soldier courses and arches over doorways and windows or red quoin corners. It takes a steady hand to reproduce this level of workmanship.
Contact M. A. Clark Brickwork for a free no obligation quote Tel: 01843 836442 or Mobile: 07866 388962