Details
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Surface |
StoneSet Premium UVR resin-bound permeable paving |
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Base |
20 mm crushed no-fines aggregate |
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StoneSet blends |
Midnight, Koonunga & Glensanda |
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Separation layer |
Geofabric |
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Design edging |
ShapeScaper steel edging |
The Project in Detail
Key Outcomes
- Retained the existing mature trees and their valuable natural canopy.
- Converted four difficult-to-maintain garden beds into robust, usable landscape features.
- Maintained rapid water infiltration to the underlying tree root zones.
- Reduced opportunities for litter and unwanted waste to collect within the garden beds.
- Introduced a reinforced paving system designed to accommodate the challenging environment around established trees.
- Created a distinctive three-colour StoneSet finish that became part of the landscape design, rather than simply covering the existing beds.
The Challenge
Earlier this year, Liverpool City Council’s design and maintenance teams set out to address a recurring challenge within Macquarie Mall, one of Liverpool CBD’s primary pedestrian thoroughfares.
Four large raised garden beds formed part of the streetscape, each containing established trees that provided valuable natural canopy over surrounding seating areas and the wider public space.
While the mature trees remained an important asset, the planted areas beneath them had become increasingly difficult to manage. Regular pedestrian interaction and disturbance meant the smaller understorey planting was struggling to establish and survive. The open garden beds were also prone to accumulating litter and other unwanted waste. This created an ongoing maintenance burden and was inconsistent with the presentation and amenity expected of such a prominent public space.
Removing the established trees simply to resolve the issue was neither practical nor desirable. Their canopy, shade and contribution to the urban landscape were worth retaining.
The challenge therefore became:
How could the garden beds be transformed into a more robust, safer and lower-maintenance public-space solution, while retaining the existing trees, supporting their ongoing health and improving the overall design of the mall?
The StoneSet Solution
StoneSet Premium UVR provided an opportunity to effectively turn the exposed garden-bed surface into a durable, permeable landscape treatment while retaining the mature trees in place.Unlike an impermeable pavement or concrete cap, StoneSet maintains an interconnected open-void structure through the finished surface.
With permeability of approximately 60 litres per square metre per second, water can rapidly pass through the StoneSet layer and into the free-draining aggregate beneath, allowing rainfall and irrigation to continue reaching the underlying root zone.
This was particularly important for the project. The objective was not simply to create a hard surface around the trees, but to do so without unnecessarily sealing the garden beds from water infiltration.
Loose litter could no longer become buried throughout vegetation or soil, while unwanted materials were far easier to identify and remove from the surface. The finished StoneSet also eliminated loose aggregate migration while still providing the visual character of natural stone.
Designing Around Established Trees
Paving around mature trees introduces a different set of considerations to a conventional pavement.
Tree root systems are dynamic. As trees mature, their roots can increase in diameter and can generate localised movement within the surrounding pavement structure.
StoneSet’s polyurethane resin-bound construction provides a impressive inherent flexibility compared with more rigid paving systems, making it well suited to applications where some underlying movement may occur.
For this project, the StoneSet surface was combined with the StoneSet Mesh & Go reinforcement system.
The triple-layer reinforcement provides additional tensile and flexural capacity beneath the StoneSet surface, helping distribute localised stresses and further improving the resilience of the pavement around the established trees.
Rather than relying on a single rigid slab, the complete build-up was designed to combine drainage, reinforcement and surface flexibility.
Turning the Solution Into a Design Feature
The Council design team took the opportunity to make the new surface an intentional part of the Macquarie Mall landscape.
Using the existing geometry of the raised garden beds, internal steel edging was introduced to divide each area into a series of defined sections.
Three StoneSet natural aggregate blends were selected: Midnight • Koonunga • Glensanda
The contrasting aggregates follow the geometry of the garden beds, producing a contemporary patterned finish while retaining the natural stone appearance appropriate to the surrounding landscape.
What began as a maintenance challenge consequently became an opportunity to introduce another visual element to the public domain.
Installation Methodology
The installation began with removal of the struggling smaller vegetation while retaining and protecting the established trees.
A geofabric separation layer was installed across the prepared garden-bed areas before the placement of the pavement base.
ShapeScaper steel edging was then positioned in accordance with the Council’s design. In addition to defining the individual StoneSet colours, the edging provided clear and durable boundaries between each section of the finished surface.
A 20 mm crushed no-fines aggregate was placed and lightly consolidated to create a stable, highly free-draining base while maintaining substantial void space beneath the StoneSet surface.
The triple-layer StoneSet Mesh & Go reinforcement system was installed over the aggregate base to provide additional tensile and flexural reinforcement across the pavement.
Finally, StoneSet Premium UVR was mixed and hand-trowelled into the individual sections using the nominated Midnight, Koonunga and Glensanda aggregate blends.
The result is a fully bound natural-stone surface that allows rapid water infiltration while providing the durability required for a heavily used CBD environment.
The Result
The completed garden beds retain the features that were worth protecting — most importantly the established trees and their natural canopy — while removing many of the maintenance challenges associated with the previous open planted areas.
Rainfall can continue to infiltrate through the pavement to the underlying root zones, while the bound surface provides a significantly cleaner and more manageable interface with the surrounding public space.
Importantly, the solution does more than address a maintenance problem.
Through the use of three natural aggregate blends and the geometry developed by Liverpool City Council’s design team, the garden beds have become deliberate architectural elements within Macquarie Mall.
It is a strong example of how permeable paving can be used beyond conventional paths and driveways — combining urban tree retention, permeability, public-space durability and landscape design within a single system.