Exposed Aggregate on the Central Coast

What exposed aggregate work on the Central Coast actually involves

Exposed aggregate is a decorative finish made by removing the top layer of cement paste so the stone in the mix shows through. The stone is chosen before the pour, by size, type and colour, and Cement Concrete & Aggregates Australia's finishes guide lists a special-class S32 mix for it. Check that your quote names both.

The stone is specified first, then the wash-off is timed

The paste is washed off soon after the concrete stiffens, once a broom no longer dislodges the stones. Drying weather shortens that window, so a surface set retarder is used on large areas and on hot, dry or windy days.

The same body recommends seven days' curing for exposed aggregate before the acid wash and any sealer. Its driveway datasheet makes seven days the minimum, not three, within a kilometre of the coast, as on a beachside street at Terrigal or Avoca Beach. Ask how long the slab will be cured.

Exposed Aggregate on the Central Coast — common questions

How is exposed aggregate priced?

This site publishes no job price. Ask the concreter for a written figure that names the aggregate you have chosen, the area and the finish, and compare quotes on that basis.

Can exposed aggregate be laid over an existing driveway?

It can, as a concrete topping bonded to the old slab, which relies on that slab for its integrity. Otherwise it means a new slab. Blasting or grinding the old surface exposes only the stone already in it.

Is exposed aggregate slippery, or rough on bare feet?

It depends on the stone and the sealer. A steep driveway may need angular crushed stone rather than rounded pebbles, and a penetrating or slip-resistant sealer, because one that forms a film can reduce grip. Around a pool, small rounded stone of 3 to 6 mm suits bare feet.