Concrete Work in Christchurch

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.

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.

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 Christchurch, ask for addresses of slabs poured a few years ago and look at the joints and edges, which is where poor work shows first.

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.

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.

Laid-and-finished flatwork typically runs NZ$100-160 per m² for plain concrete and NZ$150-250 for exposed aggregate or decorative finishes, reflecting NZ's higher materials and labour costs.