Concrete Work in Whampoa

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.

Look for crews who do concrete daily, not general handymen — finishing is a perishable skill and a two-hour window decides how the slab looks forever. In Whampoa, ask for addresses of slabs poured a few years ago and look at the joints and edges, which is where poor work shows first.

You can usually walk on it after 24-48 hours, drive on it after about 7 days, and it reaches design strength at 28 days. Curing (keeping it damp, protecting from frost or extreme heat) in the first week matters more for durability than almost anything else.

Broom (non-slip, standard outdoors), steel trowel (smooth, indoor), exposed aggregate, stamped/patterned, coloured and polished. Decorative finishes can add 30-100% to the base rate but replace the cost of a separate surface like pavers or tiles.

Common rules of thumb: 75-100mm (3-4") for paths and patios, 100-125mm (4-5") for driveways and garage floors, more for heavy vehicles — always over a compacted sub-base with mesh or fibre reinforcement. Thin slabs on soft ground crack no matter how good the finish looks.

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.