How long does repointing last?

Realistic lifespans

Lime mortar, correctly mixed, hand applied and properly cured on a period wall: 50 to 100 years. There is lime pointing on London stock brick still doing its job after a century and a half.

Cement-lime mortar on post-war brickwork in a sheltered position: 25 to 40 years.

Anything applied over damp, dirty or shallow-raked joints, or smeared across the brick face: 2 to 10 years, and it will look wrong from the first year.

What shortens it

Insufficient rake-out depth is the most common failure. If the mortar is only 5-8mm deep it has nothing to key into and it will fall out in sheets.

The wrong mortar for the wall - cement on soft brick - does not fail as pointing so much as destroy the brick around it, which is worse.

Poor curing. Lime that dries out too fast in the sun, or gets frosted in its first weeks, never gains proper strength.

Water arriving from somewhere else. A blocked gutter, a leaking downpipe or a rotten fascia will soak one section of wall continuously and take the pointing with it, no matter how well it was done.

How to get the full lifespan

Insist on hand raking, matched mortar and a sample panel you approve before the elevation is started. Keep gutters and downpipes clear and working. Deal with the roofline at the same time as the brickwork if it is tired - it is cheaper while the scaffold is up.

Then leave it alone. Sound pointing needs no maintenance at all.