Back to the drawing board saves deadline, costs

A back-to-the-drawing-board design using Echo hollow-core prestressed concrete flooring slabs has brought a rain-delayed R9-million construction project in Johannesburg back on schedule – and in the process cut R300 000 off the original budgeted cost.

Heavy rains which turned the building site into a mud-bath had threatened to seriously delay completion of major additions to St Peter’s Preparatory School in Paulshof. How the situation was turned around by the decision to use Echo slabs is told by Pierre Carter, senior contracts manager of JT Dooley Contracting, the Randburg-based main contractor of the project to build a new assembly hall, art centre and music room at the school.

The original design for the two-storey concrete-framed structure had called for conventional in-situ concrete floors, but Carter says that when unseasonable April rains stalled construction and threatened to put back the November completion date, JT Dooley’s engineering and design team had to make an alternative plan.

“We had already lost about three weeks of construction time because of the rains and we literally had to go back to the drawing board to make up that lost time,” says Carter. “We needed a Plan B – and Plan B was to consult with Echo Prestress. Between us – our client, Echo, the engineer, architects and ourselves – we redesigned the floor system to provide for Echo hollow-core concrete slabs.

R300 000 saving

“We were able to pull the construction programme back into line. But more than that – by using the Echo solution we managed to trim R300 000 off the original budget cost for the project. It’s a bonus which the school will be able to spend on higher quality specification flooring and ceiling finishes.”

Five types of slabs were used in the project in 120,150, 170, 200 and 250mm thickness.

The St Peter’s School example of how the Echo prestressed concrete slab solution can accelerate building construction – and cut construction costs – is the latest in the two-year-long association between Echo and JT Dooley. Carter says, “It’s a win-win situation all-round, built on close professional co-operation.”

Established in 1987, JT Dooley’s expertise is cast widely across the construction sector, from single-unit domestic housing to housing developments and major commercial projects, a maintenance unit and a dedicated ceilings division. The specialist division’s expertise in ceiling design and installation has won it nationwide acclaim, notably for work in high-profile shopping malls.