Honest answer: a low garden wall, a few metres of eroded joints at ground level, a patio — yes, have a go. A house elevation, a gable, anything above the first-floor windows, anything in lime — no, and not because we want the work. It's because the DIY jobs we get called to put right cost the owner more than having it done once.
What the job actually involves
Repointing isn't filling. It's four separate jobs, and the first one is the one people skip.
- Raking out. Every joint has to be cut back to at least twice its width — 20 to 25mm on a 10mm joint — and the old mortar removed cleanly to a square back. On a house that means a grinder with a mortar-raking blade and dust extraction, or a chisel and a lot of hours. Done wrong you chip the brick arrises and the wall looks worse than when you started.
- Mixing the right mortar. Not a bag of "ready-mix mortar" from the merchant. The mix has to match the brick's strength, and the colour has to match the rest of the house. Get either wrong and the repair is visible from the road for the next forty years.
- Packing the joint. Mortar pushed in firmly in two passes so it bonds to the back and sides of the joint. Smeared over the surface, it lasts about a year.
- Striking and protecting. Finished to the profile already on the house — usually weather struck round here — then kept damp and out of frost, sun and driving rain while it cures. Lime needs sheeting for days; even cement needs a couple of them.
Where DIY repointing goes wrong
The jobs we see most: joints not raked out at all, so the new mortar sits on top of the old and falls off in sheets. Hard cement used on Victorian brick, which then spalls the brick faces within a few winters. Mortar smeared across the brick faces, which stains and can't be cleaned off. And the one that costs most — someone repointing a gable off a ladder, doing a bit each weekend for a summer, then paying us to rake it all out again because the colour and the finish change every couple of courses.
When it's worth doing yourself
A garden or boundary wall under head height, where the mortar is cement, the joints are eroded rather than patched, and nobody minds if the finish is a bit rustic. Buy a proper raking blade, rake to depth, use a 1:1:6 mix (cement, lime, sharp sand) rather than a strong mix, and do it in mild dry weather. If it's stone, or the wall is old enough to have lime in it, ring us first — lime is unforgiving if you haven't used it before.
What it costs to have it done
For comparison, our guide prices start at around £45 per m² for cement repointing on brick. A weekend of DIY on a gable saves roughly the cost of the tower hire and the labour, and risks the brick. Most people who ring us have already tried a patch and decided the whole wall needs doing properly.
