Concrete Work in Kowloon City Centre

Hairline shrinkage cracks are normal; that is what control joints are for — they give cracking a straight place to happen. Wide, uneven or lifting cracks signal a base, reinforcement or curing problem. If a new slab cracks outside its joints within months, call the contractor back.

Strongly. Frost can ruin an uncured pour, extreme heat causes plastic shrinkage cracking, and rain marks fresh surfaces. Good contractors watch forecasts and will delay a pour; be suspicious of anyone happy to pour into bad weather to keep the schedule.

Surface spalling, small cracks and pitting can be patched, resurfaced with an overlay, or ground back. Slabs that have sunk can sometimes be lifted with foam or grout injection ('slabjacking') for far less than replacement. Structural failure or widespread base movement means replacement.

Concrete is priced by area and thickness for slabs (per m² or sq ft), by volume for supply (per cubic metre/yard), and by the job for repairs. The concrete itself is often less than half the bill — formwork, reinforcement, sub-base preparation, finishing and access drive the labour cost.

Excavation and sub-base, formwork, reinforcement (mesh size or fibre dose), concrete grade and thickness, the finish (broom, trowel, exposed aggregate, stamped), control joints, curing method, and spoil removal. Any quote that just says 'supply and lay concrete' leaves too much undefined.

Decades-old reinforced concrete plus humid, salty air corrodes rebar, which expands and pops the cover concrete. Proper repair means breaking out to sound concrete, treating the steel, and rebuilding with repair mortar — patching over it just delays the next fall of concrete.