Structural Support Soil

The Structural Support System is a load bearing 2-part system which provides pavement support as well as an increased root zone for street trees.

The system includes structural soil, which is a blend of blue metal aggregate with filler soil. This is designed to support pavement and provide an increased growing area for the rootzone away from the paving surface.

When installed correctly, the angular aggregate settles to meet load bearing requirements. The void spaces around the rock contain filler soil, which allows root penetration as well as providing water and nutrient retention.

The other part of the system is the Planter Mix. This provides young plants growing media to establish, and to drain excess rainwater quickly from built environments.

If the system is non load bearing, the Planter Mix can be used as a vault soil, a non-load bearing growing media for use under suspended slabs.

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  • Maximise root zones for trees to improve health and prolong life in urban situations.
  • Direct roots downwards and across into the structural soil, to minimise damage due to uplifting of the built surface.
  • Planting Mix is designed as fit for purpose product to quickly drain storm water.
  • Planting Mix can be supplied as a standard mix or customised to meet hydraulic conductivity and plant nutrient requirements.
  • Contains organic matter to maintain moisture levels.
  • Organic nutrients to support plant life.

Application Instructions

  • As per engineer’s specifications.
  • The Planting Mix will usually be installed at the volume of 1m3 for the planting hole of advanced street trees.