Cracked Driveway & Porch Slab
Repair or Recast? (2026)

Read the cracks before choosing a fix

Every concrete slab cracks a little. Concrete shrinks as it dries and moves with heat, and a porch slab poured without planned joints will crack wherever it wants to. Most of these cracks are cosmetic. The ones that matter tell you the ground underneath has moved.

Why driveways and porches crack

• No control joints. A large slab poured in one piece with no saw-cut or formed joints cracks at random. ClickBina's porch flooring guide notes that joints should be planned to control where concrete cracks.
• Water under the slab. Downpipes discharging onto the ground, leaking drains and water standing at the slab edge soften the base and wash out fines.
• Poor base. Soft fill, uncompacted earth or a thin sub-base under the slab settles under car loads.
• Load it was not built for. A lorry, a skip bin or a renovation crane on a slab designed for cars.
• Tree roots. Roots lift and crack slabs and drains near large trees; see our tree roots guide.
• Corroding mesh. Steel too close to the surface rusts, expands and pops the concrete above it.

Check whether it is still moving

Before paying for a repair, find out whether the crack is finished or still growing. A sealed crack on a moving slab simply opens again.

1. Mark each end of the crack with a pencil line and the date.
2. Check the width at a marked point with the same reference each time, such as a feeler gauge or a card edge.
3. Lay a straight edge across the crack to see whether one side is lower.
4. Check again after a few weeks of rain. Growth, a new step or new cracks mean the base is still moving.

For a new house still under its defect liability period, record the cracks and report them to the developer first; our porch and apron sinking guide explains how.

Fix the water before the slab

Most failed porch slabs on older houses have a water problem next to them. Repairing the concrete without fixing the water means paying twice.

• Connect downpipes to the drain instead of letting them discharge onto the porch edge.
• Repair cracked or broken drains alongside the slab.
• Check for a leaking water pipe under or beside the porch if one area stays damp.
• Make sure the new or repaired slab falls towards a drain so water does not stand on it.

Repair options, from small to large

Structural epoxy injection is the right tool for some cracks in beams, columns and walls, as covered in our epoxy injection guide. On a driveway it is the exception, not the rule.

When to hack out and recast

Recasting is the right answer when the slab has lost its support: sunk areas that hold water, broken pieces that rock, hollow sound over a wide area, or cracks that keep growing after the water has been fixed. A recast done properly has these steps:

1. Hack out the damaged section to straight, sound edges and remove the debris.
2. Dig out soft material and rebuild the sub-base with compacted hardcore.
3. Lay new steel mesh on spacers so it sits within the slab, not on the ground.
4. Pour the slab with falls to the drain and form or saw-cut control joints.
5. Cure it properly, keeping it damp and keeping cars off until it has gained strength.
6. Put the finish back: plain, brushed, tiled, pavers or epoxy.

If the ground is soft fill near a monsoon drain or a slope, the base may need deeper support, which is a question for an engineer.

When to call an engineer

• The porch roof, columns or the house wall next to the slab are also cracking or moving.
• The slab sits over a retaining wall, a slope or a large drain.
• Settlement keeps going after the water has been fixed.
• The porch is a suspended slab (a car porch with a room or terrace above, or a slab over a void), not a slab on the ground.

An engineer's assessment costs far less than recasting a slab twice.

What it costs

These are ClickBina's published figures (indicative 2026, Klang Valley). The total depends on the area recast, the base work and the finish.

A double porch left in plain cement rather than tiled saves RM2,000 – RM4,000 on ClickBina's porch guides, which is worth weighing when the slab is being recast anyway.

Choosing the finish after the repair

A recast is the moment to choose the porch surface you actually want. Pavers can be lifted and relaid if the ground moves again; tiles look finished but need a sound slab; plain or brushed concrete is the cheapest and grips well. Our interlocking paver guide explains when pavers make more sense than a continuous slab.

How ClickBina can help

WhatsApp us your job details for a quote: your area, house type, the rough size of the porch or driveway, the current finish, and where the cracks are. ClickBina is an experienced KL & Selangor contractor for whole-house refurbishment and coordinates drains, hacking, concrete and the new finish as one job. We reply within the hour, and the price we agree is a flat price with no hidden charges.

Sources & methodology

• ClickBina car porch and apron sinking guide — hacking, engineer assessment, epoxy injection and deeper footing prices.
• ClickBina car porch flooring options guide — tile and epoxy rates, plain cement saving, control joints.
• ClickBina factory concrete floor repair guide — epoxy mortar crack and joint repair example.
• ClickBina epoxy injection, tree roots and interlocking paver guides — related repairs and finishes.

How we estimated prices: every RM figure on this page is quoted unchanged from the ClickBina guides named above; they are indicative Klang Valley ranges for 2026.