Frequently Asked Questions Modular Retaining Walls
What is TerraStack®?
TerraStack® is a modular precast concrete retaining wall system developed by Geoquest Australia & New Zealand. Designed for residential, civil and landscape applications for efficient construction, manual handling and engineered performance.
What types of projects is TerraStack® suitable for?
TerraStack® is suitable for a wide range of applications, including:
- Residential subdivisions and housing developments
- Residential landscaping projects
- Parks, terraces and public open spaces
- Local roads, pathways and low-rise infrastructure
- Commercial and mixed-use developments
What wall heights can TerraStack® accommodate?
TerraStack® can be used for retaining walls:
- Below 1.0 metre as a gravity retaining wall (no reinforcement required)
- Up to 6.0 metres when designed as a reinforced soil structure with geogrid
How does the TerraStack® system work?
TerraStack® is a modular retaining wall system that combines:
- Lightweight precast concrete facing panels
- Purpose-designed precast concrete counterforts
- Geogrid soil reinforcement (for walls above 1.0 metre)
- Compacted structural fill
Do I need cranes or heavy equipment to install TerraStack®?
No crane is usually required. TerraStack® panels weigh less than 25 kg, making them suitable for manual handling. This reduces plant requirements and simplifies installation, particularly on constrained or residential sites.
How is TerraStack® different from traditional retaining wall systems?
Compared to traditional systems (such as large concrete blocks or in-situ walls), TerraStack® offers:
• Smaller, lighter panels for easier handling
• Faster installation with fewer components per square metre
• Reduced concrete usage
• Lower transport and installation costs
• A refined, architectural finish
Is TerraStack® an engineered solution?
Yes. TerraStack® is fully engineered and designed in accordance with AS 4678 (Earth-retaining structures). It is supported by Geoquest’s research, development and full-scale testing, ensuring predictable performance over its design life.
Can TerraStack® be customised for different site conditions?
Yes. Geoquest provides project-specific design services, including:
- Concept and detailed design
- Engineering verification
- Site-specific reinforcement layouts
Each TerraStack® solution is tailored to meet the requirements of the project, including height, loading conditions and geotechnical parameters.
What aesthetic options are available?
TerraStack® offers a clean, contemporary finish suitable for both residential and public environments. Options include:
- Custom textures and surface finishes
- Flexible panel layouts
- Paintable surfaces for colour matching
- Anti-graffiti coatings
Is TerraStack® a sustainable solution?
Yes. TerraStack® supports more sustainable construction outcomes by:
- Using less concrete compared to traditional systems
- Reducing material consumption
- Lowering transport impacts due to lighter components
- Delivering durable, long-term performance
Who can install TerraStack®?
TerraStack® is designed to be practical and accessible for:
- Civil contractors
- Builders
- Landscapers
- Specialist retaining wall installers
Geoquest can also provide guidance and support during construction.
What support does Geoquest provide?
Geoquest offers full project support, including:
- Design and engineering services
- Technical advice during construction
- Compliance with relevant standards
- Decades of expertise in reinforced soil structures
Is TerraStack® available across Australia and New Zealand?
Yes. TerraStack® is available throughout Australia and New Zealand, supported by Geoquest’s local teams.
How do I get started with TerraStack®?
To discuss your project and discover more about TerraStack®, contact your local Geoquest office. Our team can provide tailored advice, preliminary design guidance and project-specific solutions.
Read more about the modular retaining wall solution here.
Contact
To speak to our engineering and project management team about your modular retaining wall needs contact your local Geoquest office.
