03/10/2026
Technical Deep Dive: King Post Walls
Due to challenging site topography and ground conditions, the originally proposed pushed sheet pile solution was ruled out. Driven sheet piles were also deemed unsuitable due to the potential ground disturbance and vibration, particularly with residents, a school, church, nursery and casino in close proximity.
Working collaboratively, the site and design teams developed a King Post Wall system to retain the existing ground and allow ground-lowering works to safely progress on the opposite side.
The design was developed by our structural engineers in conjunction with ESS (CE) Ltd, incorporating 10m-long steel columns (305 × 305 × 118kg UCs) with 140mm concrete panels installed between the posts.
The installation involved CFA piling the designed locations, filling each pile with concrete to 3m below ground level, and craning the steel columns into position. Once the concrete had cured, temporary steel plates were installed to the rear of the columns to retain the existing ground while excavation took place for the concrete panels.
Following panel installation, the temporary plates were removed and any voids were backfilled.
The completed King Post Wall provided the required ground retention, enabling excavation for the new building foundations to proceed.
The accompanying photos showcase the design, installation process and completed works.