Driven Timber Piles under Concrete Slab Foundation // NZ Builder

What do you do when the ground your building on is too soft to handle the foundation load? One of the options is to drive timber piles in until they hit “Good Ground“ That’s exactly what we did on the townhouse job. We drove x72 150mm SED Timber piles to an average depth of 3.1 - in preparation for our concrete slab. The Piles are H5 Treated Good ground is defined in NZS 3604:2011 Timber-framed buildings as soil that has an ultimate bearing pressure of 300 kPa. Evidence of good ground includes where: foundations of adjacent buildings show no signs of settlement or inadequate bearing there is no evidence of landslides in the vicinity there is no evidence of buried services there is no organic soil, peat or soft clay. Re: Using Timber in the Ground From NZ Wood... The piles are expected to be permanently below ground level after construction. The groundwater level is expected to be not far below the tops of the piles. Woo