If your paving has sunk, the honest answer is usually lift and relay the affected area rather than patch it — but only after you have worked out why it sank. A dip is not a paving fault. It is the surface telling you something failed underneath, and if you relay the blocks without fixing the cause you will be looking at the same dip in two years.
The good news is that paving is repairable in a way that a poured slab is not. The blocks themselves are almost always fine and reusable. What you are paying for is the labour to lift them, rebuild the layer beneath and put them back — which is why a localised repair is genuinely much cheaper than a new driveway, provided the problem really is localised.
Work out why it sank first
The shape and location of the damage tells you most of what you need to know.
| What you see | Most likely cause | What it means for the repair |
|---|---|---|
| Two parallel troughs where car wheels track | Sub-base too thin, too weak or never compacted properly | Lift and rebuild the base to full depth, not just the sand |
| A single localised hollow | Fines washed out by a leak or concentrated run-off; or backfill over a trench settling | Find the water source or the trench first, then relay |
| Dip along one edge, joints opened | Failed or missing edge restraint; blocks spreading sideways | Install proper haunching or a kerb, then re-lay and re-sand |
| Sinking right at the garage door or gate | Poorly compacted fill in a service trench, or the transition never built up properly | Excavate deeper than the trench depth and rebuild in lifts |
| Long low wave across a wide area | Bedding sand far too thick, migrating under load | Full lift and relay of the area with a correct thin bedding layer |
| Dip near a downpipe or channel outlet | Water discharging under the paving and scouring the base | Fix the drainage before touching a single block |
| Blocks rocking, joints empty, no real dip yet | Jointing sand lost — often after pressure washing | Re-sanding only. Do not over-engineer this one |
Notice how many of those come back to water. In a winter-rainfall city, water moving where it should not is the leading cause of base failure. Standing outside during a decent cold front and watching where run-off actually goes is the most valuable ten minutes you will spend on this problem — our guide to driveway drainage in winter rain covers what to look for.
Local soil, local causes
Sandy areas — Table View, Blouberg, Parklands, Milnerton and across the Cape Flats. The usual failure is a thin stone layer that has mixed into the loose sand until it is no longer a structural layer at all, or bricks laid essentially on sand from the start. Repairs here need real depth and usually a geotextile separator so the new stone stays separate from the sand. Cracking and settlement causes are covered further in our guide to driveway cracking causes and fixes.
Clay areas — parts of Durbanville, Brackenfell and the Tygerberg side. Clay swells in the wet winter and shrinks in the dry summer, and Cape Town’s climate drives that cycle hard. Paving over reactive clay moves seasonally. Sometimes a dip that appears in September has partly recovered by February, which is a strong clue. The answer is a thicker sub-base to bridge the movement, plus drainage that keeps water away from the clay in the first place.
Sloped properties — Plattekloof, Hout Bay, Constantia, Vredehoek. Sheet flow from higher ground scours fines from under the paving and the bottom edge takes the strain of vehicles braking. Repairs here usually need a cut-off drain uphill as much as they need new stone.
Repair, relay or replace?
Re-sand only
Right when joints are empty and blocks feel slightly loose, but the surface is still true. Cheap, quick, and it restores the interlock. It is the wrong answer if there is a genuine dip — sand does not fill a structural void.
Localised lift and relay
The workhorse repair, and the right answer in most cases. The blocks over the affected area are lifted and stacked, the bedding sand removed, the sub-base rebuilt to correct depth and compacted in lifts, the falls re-established, and the same blocks re-laid and re-jointed. Because the pavers are reused, material cost is minimal.
Two things determine whether it looks like a repair or looks invisible: whether the crew keeps the original blocks in order and orientation, and whether they extend the repair to a sensible line — a joint line, a border, a change of pattern — rather than stopping at a ragged edge. Expect some colour difference regardless: relaid blocks have weathered, and any replacements will not match. Taking the odd replacement block from an inconspicuous area and putting the new ones there instead is an old trick that works.
Full lift and relay
Needed when the failure is across the whole area — base never built, bedding sand used as a base, or the surface waving over most of its extent. Published Cape Town figures put a lift and relay at around R380–R650 per m², typically 40–60 percent of a full replacement. It is a big job but it keeps your existing blocks, which is a substantial saving and the greener option.
Full replacement
Only worth it when the blocks themselves are worn out, broken in quantity, or you want a different material or layout anyway. Replacement with new material runs roughly R650–R1 600 per m² depending on the material chosen. If you are at this point, our Cape Town paving prices guide sets out what each material costs installed.
What the repair actually involves
- Diagnose. Identify the water path or load path that caused the failure. Skip this and you are budgeting for a second repair.
- Mark a sensible boundary for the work — extend at least half a metre past the visible dip in every direction, because the weak base extends past the visible symptom.
- Lift and stack the blocks, keeping them in order where the pattern matters.
- Remove the bedding sand and dig out the failed base down to sound material.
- Fix the cause. New channel drain, cut-off drain, repaired leak, geotextile separator, deeper excavation — whatever the diagnosis called for.
- Rebuild the sub-base with graded stone, placed and compacted in lifts, shaped to the finished falls.
- Screed a thin bedding layer — 25–40mm, not more.
- Re-lay the blocks, cut in any replacements, compact with a protective mat.
- Sweep in dry jointing sand, compact, sweep again, and top up a few weeks later.
- Reinstate or install edge restraint on any free edge involved.
That sequence is the same work as building it properly the first time, which is why it costs what it costs. Our installation and prep guide goes through the layers in more detail.
What about the DIY route?
A small dip — a square metre or two, on a patio, no vehicles involved — is a genuinely reasonable weekend job. Lift the blocks, dig out, add and compact graded stone in thin layers, screed sand, relay, re-sand. A hired plate compactor makes the difference between a repair that lasts and one that sinks again.
Where DIY reliably goes wrong: people top up with bedding sand instead of stone, or compact one thick layer instead of two thin ones. Both give you a surface that is level on Sunday evening and dipped again by winter. And on a driveway, the loads and the depths involved are beyond what hand tools will achieve.
Costs to plan for
- Lift and relay: roughly R380–R650 per m², around 40–60 percent of full replacement.
- New paving: roughly R650–R1 600 per m² installed depending on material.
- Adding a channel drain at a garage line: roughly R4 000–R12 000.
- Full drainage redesign as part of a relay: roughly R8 000–R25 000 on top of the paving cost.
- Rubble removal if material has to leave site: a skip in Cape Town runs roughly R1 200–R2 000.
Two cost-control points. First, a small area repaired early is far cheaper than a large one repaired late — a modest patch left alone through a couple of wet winters becomes a lift measured in tens of thousands. Second, if you are having anything lifted anyway, that is the moment to add drainage. Doing it later means lifting twice.
How to judge a repair quote
- Does it name a cause, or does it just say “relay sunken area”? A quote with no diagnosis is a quote for a temporary fix.
- Does it specify excavation depth and sub-base material and compacted thickness?
- Does it include re-establishing falls, not just re-levelling to the surrounding paving?
- Does it include edge restraint where an edge is involved?
- Does it mention jointing sand and a follow-up top-up?
- Does it say what happens to blocks that break during lifting?
- Is anyone proposing to fill the dip with sand and put the blocks back? That is not a repair, and you should not pay for it.
Getting it looked at
Most sunken paving we see is fixable as a localised job, and finding that out costs nothing. If your driveway has a dip, a rut or a rocking patch, have a look at our our paving repair service and send through a photo — the shape of the damage usually tells us what is going on before we arrive.
Quick answers
Can sunken paving be repaired without replacing it?
Almost always. The blocks are lifted and reused, the failed base is dug out and rebuilt with compacted graded stone, and the same pavers go back down. Lift and relay typically costs 40–60 percent of full replacement.
Why does paving sink in one spot?
Usually water. A leak, a downpipe discharging under the surface or concentrated run-off washes fines out of the base and it collapses. Settling backfill over a service trench is the other common cause, particularly near gates and garage doors.
Is it worth patching or should I relay the whole driveway?
Patch if the failure is localised and the rest of the surface is true. Relay the lot if the surface waves over most of its area, because that means the base or the bedding layer was wrong from the start and patching just chases the problem around.