Tuckpointing vs Repointing: What the Terms Mean
Repointing means cutting out deteriorated mortar and packing the joint with fresh mortar. Tuckpointing, in its original sense, is a decorative technique where a thin ribbon of contrasting lime putty is set into colored mortar to fake fine joints. In St. Louis and most of the Midwest, contractors say tuckpointing when they mean repointing, so ask what the scope covers rather than reading the word.
Two masons can quote the same wall, one writes “tuckpointing” and the other writes “repointing,” and the work they have in mind is identical. A third writes “tuckpointing” and means running a bead of mortar over the surface without cutting anything out. The words will not tell you which is which. The scope will.
Where did the word tuckpointing come from?
Tuckpointing started in England in the 18th century as a way of making ordinary brickwork look expensive. Fine gauged brickwork with hairline joints was the prestige finish and it was slow and costly. So bricklayers cheated. They pointed a wall in mortar colored to match the brick, then cut a narrow groove and pressed in a thin ribbon of white lime putty, tucked into the groove and trimmed straight. From the street the wall appeared to have precise, hairline white joints.
That is tuckpointing in the strict sense: a decorative two-part finish. It still exists on historic buildings, and restoring it is specialist work.
Repointing is the maintenance job. Deteriorated mortar comes out, fresh mortar goes in, the joint is tooled to match the original profile. The Park Service brief on the subject notes that the American trade uses “tuck pointing” loosely for this, and that is exactly what happened here. In St. Louis, tuckpointing means repointing. Nobody is going to change that, and you do not need them to.
What do the words actually cover on an estimate?
Since the label is unreliable, read for these five things instead.
| Term you might see | What it should mean | Question to ask |
|---|---|---|
| Repointing | Old mortar cut out to depth, joint refilled and tooled | How deep is the cut? |
| Tuckpointing | In St. Louis, the same as repointing | Same question |
| Spot pointing | Only the failed joints, sound joints left alone | What percentage of the wall? |
| Skim or surface pointing | Mortar smeared over failed joints with nothing removed | Avoid. This fails in a few winters |
| Grinding and pointing | Joints opened with a power grinder before filling | Are head joints done by hand? |
If the estimate is one line and one number, none of these questions have answers yet. Ask for the breakdown.
How deep should the joint be cut?
This is the single number that separates real repointing from cosmetic work. The accepted guidance, and what the Cultural Resources Office asks for in city historic districts, is to remove mortar to a depth of roughly two to two and a half times the width of the joint.
Run the arithmetic on a typical wall. A 3/8 inch joint gets cut back to about three quarters of an inch to an inch. A quarter inch joint gets cut to about half an inch. The point of the ratio is mechanical. New mortar needs enough depth to key into the joint and enough surface area on the brick to bond. Below that ratio the plug is too shallow to hold and the freeze-thaw cycle levers it out.
Also cut back until you reach sound mortar. If the joint is soft an inch and a half in, the cut goes to an inch and a half. Stopping at the ratio and leaving mush behind gives you a hard shell over a failed joint.
Is a grinder acceptable?
Yes, with limits. An angle grinder with a dust shroud is efficient on long straight horizontal bed joints and can be run accurately by someone who does it every day.
The problems start on the vertical head joints. Those are short, often only a couple of inches, and a circular blade cannot reach the bottom of one without cutting past its ends into the brick above and below. Head joints should be done with a hand chisel or a small oscillating tool. If you look at a wall and see short vertical overcuts running into the brick faces above and below every head joint, a grinder was run where it should not have been.
Two other things to watch. The blade must be narrower than the joint, otherwise the joint gets widened permanently and the wall ends up with fat, out-of-scale mortar lines. And grinding generates silica dust, so a shroud and vacuum should be on the tool.
What does the joint profile have to match?
The shape you tool into the finished joint is part of how the building looks and part of how it sheds water. Common profiles on St. Louis buildings:
- Concave. Pressed with a rounded jointer. The default on most 20th century work and good at shedding water.
- Weathered. Angled so the top of the joint is recessed and the bottom projects. Sheds water well and is common on older street elevations.
- Flush. Struck level with the brick face. Frequent on side and rear walls and on utilitarian buildings.
- Grapevine. A shallow groove run down the center. Shows up on some 19th century work.
- Raked. Recessed square. It looks sharp and it holds water on the ledge, so it belongs indoors or under cover.
Match what the building has. A concave joint tooled onto a wall that was originally flush changes how every shadow on the elevation falls, and in a local historic district it can be a compliance problem rather than a taste problem.
How do you tell good work from bad after the fact?
Walk the finished wall in low, angled light. Look for these.
- Joint width unchanged from the original, with no widened bands where a blade wandered
- Brick arrises sharp, with no chipped edges above and below the head joints
- Mortar filling the joint fully with no voids at the back of the recess
- A consistent profile across the whole elevation
- Color reading close to the original once cured, which takes a few weeks
- No mortar haze smeared across the brick faces
- Head joints tooled to the same profile as the bed joints
Fresh mortar always looks brighter than the wall around it. Judge color after a month of weather rather than on the day the scaffold comes down.
Does any of this change on a Webster Groves house?
The stock changes, so the work changes. A lot of Webster Groves housing is frame or brick veneer sitting on a limestone or brick foundation, and the foundation is often where the pointing is needed. Stone joints are wider and more irregular than brick joints, so the two-times-the-width rule produces a deeper cut, and the mortar has to be soft enough to suit the stone.
Chimney stacks on those houses also tend to be tall and exposed, which is why they fail first even when the walls below are fine.
What to ask for in writing
Whatever the estimate calls it, the scope should name the depth of cut, the mortar type, the joint profile and how head joints will be opened. Our written scopes carry all four, and the tuckpointing page walks through how we handle each one. Bring us an estimate you are unsure about and we will tell you what it leaves out.