Waffle slab floors have been used in New Zealand for about a decade.
The system consists of an on-ground reinforced concrete slab supported on a grid of reinforced concrete ribs on a level building surface. Polystyrene pods are used as formers between the ribs.
One such system is the Voidform waffle raft slab system. Barnes Plastics sales manager Peter Grainger says the Voidform system has several advantages over conventional foundation construction methods.
“It is a simple, quick method of construction. Less site preparation is required and it has fewer stages, all of which can be carried out by one trade.
“Only one concrete pour is required, and concrete volumes can be accurately calculated. Work can often continue in adverse weather conditions – there are no trenches to fill with water. Quality control is simple, and Voidform provides a high level of built-in insulation,” he says.