6 min read · Updated 18 July 2026
Sinking Block Paving: Why It Happens and What Repair Really Costs
A sinking block-paved drive is almost never a jointing-sand problem. It's a sub-base problem, and the cost gap between a spot repair and a full re-lay is the difference between £280 and £4,800.
Three real causes of block paving sinking
1. Sub-base too thin at install (the most common - a 50-75mm layer of Type 1 that should have been 150-200mm).
2. Sub-base washed out by an unmanaged drainage source (a leaky downpipe, a dead soakaway, or run-off from a neighbour's plot).
3. A trench under the drive that wasn't compacted in layers when a utility was installed or replaced.
Spot repair vs full re-lay - how to tell
Localised dip of 1-3 blocks and the rest of the drive is flat? Spot repair: lift the blocks, re-lay the sub-base in that patch, re-bed. £280-£650.
Multiple sunken areas or a full wheel-track depression? The whole sub-base was built too thin. Full re-lay: £110-£165/m². Spot repairing this pattern just moves the problem.
The drainage question
Before spending anything on the paving, we check: is there a downpipe discharging onto the drive? A cracked gully? A soakaway that's collapsed? Fixing the water source is 30% of the fix. Ignoring it means the same repair sinks again inside 3 years.
Cost bands (2026, Surrey/Hants)
Spot re-lay of 1-3 blocks including sub-base rework: £280-£650.
5-8m² area re-lay: £900-£1,600.
Full drive strip and re-lay (60-80m²): £6,800-£13,200.
Drainage remediation (soakaway, gully, downpipe re-route): £450-£2,400 depending on scope.