How to Install Root Barrier

What is a root barrier?

A root barrier is a flexible HDPE membrane measuring just 1mm thick. Root barriers are ideal for controlling root growth in any application, from housing developments to major infrastructure.

A durable and lightweight solution for controlling unwanted root movement and growth, its light weight allows the root barrier to be cut and shaped to suit your requirements. Once in place, the barrier creates a long lasting seal to trap root and moisture. This promotes healthy tree growth without the tree causing damage to surrounding structures.

Why use root barrier?

Invasive tree root growth can become an issue along nature strips, in landscaped industrial areas, and alongside roads and footpaths. When tree roots naturally spread and grow around pipes and under pavements and driveways, they can cause damage to the man-made structures around them, costing time and money to repair.

An effective way to control the spread of unwanted root growth is to install a root barrier during the tree planting process. Root barrier can be installed in a circle around the tree, and also in a linear fashion alongside pavements.

How do you install root barrier when planting trees?

When you have dug a large hole and planted your tree, place the root barrier around the edge of the hole and measure the correct length to cut, allowing for some overlap. Once you have the right length, install the barrier so that the top is level with the surface of the soil. If you need to join the two ends of your root barrier it can be joined by using a product such as butyl tape.

It’s important to try not to restrict the soil volume the tree can access, as this can create an unbalanced and potentially unsafe root system. Australian Standard AS 4970:2009 Protection of trees on development sites makes reference to the structural root zone (SRZ) of a tree, and this can be used for guidance when determining how large the hole should be.

How do you install root barrier near pavements and footpaths?

First, measure the length of the pavement along its edge, as the root barrier needs to be installed adjacent to the edges of the path, driveway or concrete slab. Dig a trench parallel to the pavement to prevent tree roots from growing directly underneath it. The trench should be larger than the root barrier, allowing for some room around the edges.

Place the HDPE root barrier in the trench and backfill around it. This will prevent tree roots from encroaching under the pavement. Once again, refer to the guidelines on structural root zones to make an informed decision on how and where to install your root barrier. 

Buy root barrier or find out more

A smooth, continuous, non-ribbed and non-dimpled root control solution, the GEOmasta root barrier is ideal for larger applications such as infrastructure and landscaping projects. This lightweight yet strong barrier layer comes in widths from 600 to 1200mm, in 30 metre rolls.

For more information or to get a fast quote, contact our friendly GEOmasta team.