Brick repairs & repointing in Melbourne

After, essentially always. Brickwork repair is the last step, not the first. If the ground under the house is still moving, a stitched or repointed crack will simply reopen — usually within a season or two — and you will have paid twice. The correct order is: diagnose the movement, stop or stabilise it, allow a period to confirm it has stopped, then repair the masonry. The only exception is where a crack is admitting water into the building, in which case a temporary weather seal is sensible while the structural question is resolved.

Crack stitching bonds helical stainless steel bars into the horizontal mortar joints across a crack, using a thixotropic grout, so the masonry regains tensile continuity across the break. The bars are hidden inside the joints, so once repointed the repair is invisible. It is used where a structural crack has broken the continuity of the brickwork and the wall needs to act as one piece again — typically stair-step cracking from settlement or heave, once the movement has been dealt with. It is not a substitute for fixing the cause; it restores the wall after the cause is fixed.

Run a key or a screwdriver along a mortar joint. If the mortar is sound it will resist; if it crumbles, powders or you can rake it out to any depth, the pointing has perished. Other signs are mortar visibly recessed behind the brick face, joints that have washed out on weather-exposed elevations, sand collecting at the base of the wall, and damp appearing internally on a wall with open joints. Perished pointing matters beyond appearance — open joints let water into the wall, and water in the wall is what corrodes wall ties and drives frost and salt damage.

Because cement mortar is harder and less permeable than the bricks around it, and in a solid-brick wall built with lime mortar that reverses how the wall is designed to work. Lime mortar is intentionally the sacrificial, softer element: it lets moisture evaporate out through the joints and it accommodates small movements without cracking the bricks. Point that wall in a hard cement mix and the moisture and the movement are forced through the bricks instead, so the brick faces spall and blow. On pre-war solid brickwork — most of Melbourne's period housing — a lime-based mix matched to the original is the correct specification, and it is worth insisting on.

Yes, and it is routine. Individual spalled, cracked or blown bricks are cut out and replaced with matched bricks in a process called piecing-in. The technical part is the match rather than the work: Melbourne has an enormous range of historical brick types, colours and sizes, and a bad match is more visually obvious than the damage was. Reclaimed bricks of the right era are usually the answer on period housing. On a large area, a bricklayer will sometimes take bricks from a hidden elevation to patch a visible one and use new bricks where they will not be seen.

Fresh mortar will always be slightly different from mortar that has weathered for eighty years, and any tradesperson who promises an invisible match is overselling. What good work does is get close enough that it stops reading as a repair: matching the mix colour and the sand, matching the joint profile — struck, raked, flush or ironed — and matching the joint width. Those three things matter more than the mortar colour on day one, because the colour blends over a couple of seasons and a wrong joint profile never stops looking wrong.