Stratacell™ represents the fifth generation of root cell and has been developed and patented globally by Citygreen® Systems. Stratacell builds on the experience gained through trials, projects and collaborations with industry innovators. The main drivers have been the need for lower installation costs, higher strength, reduced transport costs and maintenance of large spaces for root growth.


  • Modules assemble to form an interconnected matrix, so applied loads are shared evenly and lateral strength maximized.
  • In excess of 94% of total soil volume is available for tree-root growth
  • Generously designed apertures permit common conduits, service pipes and aeration systems
  • Long-term root-zone management is possible when installed in conjunction with Citygreen’s RootRain & Root Director (as shown)
  • Made from 100% recycled polymers; ensuring maximum environmental benefit & ‘Green Building’ contribution
  • Modules ‘snap-together’ incredibly fast, providing super-efficient assembly time on site (records show it takes approx 2 mins/m³!)
  • No zip ties, screws, ground spikes or lids required to fasten this system together; again providing super-fast and ‘hassle free’ assembly on site.
  • Made in strategic locations in North America and Australia; supporting local industries and complying with green building requirements.
  • Modules are designed to nest, giving significant volume reduction, and minimising shipping costs.
  • Ultra-Strong modules are available, and can be used closer to the surface. These are up to three times as strong as anything else on the market.
  • Lower strength modules are also available – which are still 40% stronger than any other product of this type on the market – suits more costs sensitive projects.
  • No steel components required for strength; therefore nothing to rust or corrode
  • Compact module design works well with confined or difficult treepit sizes
  • Continuous physical laboratory tests of strength are conducted to ensure integrity of modules and quality assurance. Whilst FEA testing (Finite Element Analysis) is great during the design stages, we prefer to go by real life static and cyclic load testing in laboratories.


Assembling High Strength Structural Soil Cells in ScandinaviaStratacell has been designed to achieve major reductions in installation costs. Units snap together quickly and easily, with labour times being drastically reduced.

Positive and secure connectors are a feature of the Stratacell patented design both vertically and laterally. Stratacell modules are simple and fast to click together, producing an integrated matrix.

Volume reduction for freight

Another unique design feature of the Stratacell module is the significant volume reduction for freight. With increasing scrutiny placed on use of fossil fuels and shipping costs, it was decided that this unit must achieve major volume reductions for shipping. The innovative nesting design is protected by worldwide patents and design registration, as are all other design features.

Recycled Content

The Stratacell is a very highly engineered module that owes much of its incredible strength to a unique design (subject to numerous patents). So strong is this design, that the base model Stratacell (Series 30) has an ultimate strength in excess of 300kPa/43.5psi without relying on any steel bars (subject to corrosion), or glass reinforcement, or virgin resins.

This module is 70-100% stronger than other brand soil cells, and is made entirely from recycled Polypropylene. Due to the emphasis Citygreen places on environmentally sustainable systems, over 400,000 kg of plastic are saved from landfill every year.

The top model Stratacell (Series 60) has an ultimate strength of 600kPa/87psi, and is manufactured from a unique blend of recycled PP and glass fibre. Capable of withstanding heavy traffic loads, the Series 60 Stratacell is the world’s strongest large soil cell by a huge margin.

Physical load testing of the Stratacell Gen

Structural Integrity

Stratacell modules are crush tested during manufacture as part of the rigorous quality control standards required by Citygreen. Whilst FEA (Finite Element Analysis) computer load testing was also conducted during the initial design stages to project the loading capacity laterally and vertically, physical laboratory tests were then used to clarify the cells actual loading capabilities.

This physical load testing is part of an ongoing development and research program, and is the only true measure of structural integrity. Stratacell modules are made using 100% recycled polypropylene, and have the highest structural integrity of any large soil cell.

Fatigue Testing

As the world’s strongest large soil cell, Stratacell has been subjected to extraordinary laboratory tests, including fatigue testing. In one test a university applied a load of 8.6 tonnes to a Stratacell tower 10,000 times. The tower was then crushed to measure whether the ultimate load had been diminished by the cyclic loading. The high strength modules had lost no strength, verifying the design strength of this remarkable system.

Energy Use

The use of virgin resins in a product for the Green Building Industry has never been a part of the Stratacell development program. Virgin plastics have an unacceptably high level of embodied energy, whereas recycled waste plastic into an engineering grade product starts with a clean sheet as recognized by industry and the Green Building Council.

Products-and-Solutions_21-230x119 stratacell_gen5_top-226x160 StrataCell Gen 5 3x3 stacked images 226x160 150x150 1 Citygreen

Product Specification

Product Code Description Dimensions Material Load Capacity
60 Series SC250 Recycled plastic rigid skeletal interlocking octagonal structure 510mm x 510mm x 250mm (20″ x 20″ x 10″) Advanced glass reinforced polymer 600Kpa/87psi vertical load
30 Series SC250 Recycled plastic rigid skeletal interlocking octagonal structure 510mm x 510mm x 250mm (20″ x 20″ x 10″) Advanced polymer 300Kpa/43.5psi vertical load
*Note: Product dimensions may change without notice. Please confirm with Citygreen at time of order placement.

Supported Products

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The Citygreen Stratacell can be easily used within any HydroCAD Stormwater Modeling System, model for stormwater storage, detention, or infiltration. The HydroCAD Chamber Wizard also performs automated chamber system layout, and simplifies the process of designing a chamber system meeting specific storage and footprint requirements. Click here for details.

HydroCAD® is a registered trademark of HydroCAD Software Solutions LLC.

“Great customer service, quick response times and a very in depth QA system with constant support.”

- Laura Wiesenekker, Project Engineer, Densford Civil -

“Citygreen is a very professional  business, and I found everything was great in terms of deliveries, product supply and information. It was all forthcoming and helped us to complete the project.”

- Keith Burns, Architect/Designer, Keith Burns Architect -

“Citygreen offered training and invaluable technical assistance during the works.”

- James Callan, Estimating Manager, Complex Co Pty Ltd -

“Our experience, in working with a Citygreen Design Studio was second to none. We found responses from the design studio to be very timely, and technically thorough. We went backwards and forwards a number of times, looking at different iterations of the design and, nothing was too much trouble to examine and explore different possibilities. I would highly recommend the Citygreen Design Studio to any future client considering using your services.”

- Sandra Smith, Principal Landscape Architect, City Of Monash -

“We are big on compliance on all projects, and the fact that their SmartCertify cloud platform covers all bases, and supports their 20 year warranties, is critical – especially that these pits are being installed under roadways and footpaths.”

- Johny Purkaystha, Civil Program Engineer, Central Coast Council -

"I reviewed all the previous projects that we have installed in the past couple years using your product and I can happily report back that we have 0% mortality in the soil cells, which is incredible!"

- Brendan Wilton, CEO, Trim Landscaping, Bedford, Canada -