Project Overview

GB Card & Partners (GBCP) delivered an innovative foundation solution at the former Erith Quarry in Kent, enabling the development of a major brownfield site previously considered unviable.

• Location: Erith, Kent
• Development: 850 homes, primary school, retail and commercial space
• Project Value: Approximately £300 million
• Ground Conditions: Up to 28m of landfill, including hazardous materials
• Solution: CARD DECK® hybrid raft foundation system

The Challenge

The Erith Quarry site presented exceptionally challenging ground conditions, with up to 28 metres of landfill comprising inert, biodegradable, and hazardous materials, including asbestos.

The ground was highly variable and compressible, with predicted settlement of up to 2,000mm. In addition, the site required careful management to protect surrounding aquifers from contamination.

• Extreme variability of the ground
• Environmental constraints
• High cost and programme implications

The Solution

GBCP introduced its patent-pending CARD DECK® system — a hybrid raft foundation designed specifically for challenging ground conditions.

The system combines a high-strength upper layer with a granular lower layer to form a flexible composite raft, enabling effective load distribution while accommodating ground movement.

CARD DECK® was configured into modular podiums, providing a scalable solution for a range of building types.

Delivery

The modular design enabled efficient installation, reducing reliance on heavy plant and extensive ground intervention.

By avoiding deep piling and minimising concrete use, the solution reduced complexity, environmental impact, and improved programme certainty.

Results

• Enabled development of a 20-hectare site including 850 homes, a school, and commercial space
• Accommodates significant settlement while maintaining structural integrity
• Minimises disturbance and protects aquifers
• Reduces carbon-intensive materials
• Accelerates construction and improves cost certainty

Client Feedback

“The hybrid rafts were a stroke of genius, and the development has been a complete success.”

Ian Cunnane, Operations Director at Anderson

Conclusion

The application of CARD DECK® at Erith Quarry demonstrates how innovative foundation engineering can unlock complex brownfield sites.

The system provides a scalable solution for future projects, delivering economic, environmental, and social value while maintaining technical excellence.

For further information contact info@gbcardandpartners.com