Pointing and joint profile

Frequently asked questions

Does tuckpointing mean repair or decoration?

Both, depending on which side of the Atlantic the specification was written on, and they are not related operations. In AMERICAN usage tuckpointing means repointing: raking out failed mortar and replacing it, which is repair work priced by the square metre of wall and the depth cut out. In BRITISH usage tuck pointing is a decorative finish from the eighteenth and nineteenth centuries — the joint is filled with a mortar coloured to match the brick, and a fine ribbon of white lime putty is then tucked into a groove cut in it, so that the wall appears to be built with far finer joints than it is. It is highly skilled, it is slow, and it appears on buildings where the imitation of gauged brickwork was the point. Quoting one against the other is an order-of-magnitude pricing error in either direction.

Which profile sheds water best, and does it matter?

It matters a great deal on an exposed wall and hardly at all on a sheltered one, which is why the choice is usually made on appearance and then regretted on one elevation. A WEATHER STRUCK joint is cut back at the top and left proud at the bottom, so water runs off the sloping face and away — it is the most weather-resistant traditional profile and it is why it dominates on exposed British elevations. A BUCKET HANDLE or concave joint is compacted with a rounded tool, which densifies the mortar surface and sheds reasonably while being far faster to form. A RECESSED or raked joint is the worst: it creates a ledge on every course that holds water and, in a freeze, ice. It also reduces the joint's cover over the masonry. It looks excellent, and on a wall that gets weather it is a maintenance decision.

Why does raking out too deep, or not deep enough, both fail?

Because new pointing has to have enough depth to grip and enough sound mortar behind it to grip onto. Rake out too SHALLOW — a common shortcut, cutting perhaps five millimetres — and the new mortar is a thin skin with very little mechanical key, which falls out in sheets within a few years and takes the face of the brick with it if it was too strong a mix. Rake out too DEEP, or with an angle grinder that widens the joint and scores the brick above and below, and you have removed sound material, enlarged the joint so the wall reads wrong, and cut the arrises off the bricks permanently. Guidance generally puts the depth at around twice the joint thickness, cut square and by hand on anything old, and the grinder is the tool that has destroyed more historic brickwork than weather has.