Foundations and Excavation Support

We are widely experienced in the design of cofferdams, temporary retaining walls, temporary, and permanent foundations. A selection of relevant past projects is given here. Further details can be found on our Temporary Works, Structural Design and Past Projects pages.


St Germans Pumping Station, Norfolk

We were engaged by the main contractor Costain to design strutting frames and temporary ties for use during construction of a large cellular cofferdam.



Origin, Princess Street Manchester

We were engaged by West Contracting to design a ground level strutting frame to support the bored pile wall of a 12 metre deep basement excavation in central Manchester. The tubular steel props were up to 1016mm diameter and 44 metres long.


Port Solent Marina Lock Cofferdam

David Ellis acted as contractor’s site agent for Geoffrey Osborne Ltd. and re-designed the temporary strutting frame for this cofferdam.



Nam Cheong Station, Hong Kong.

Detailed design of propping scheme to support a sheet piled excavation 400 metres by 100 metres by 16 metres deep. The props reacted against the permanent structure which was constructed top down.


Touchwood Court, Solihull

Design of propping frames to secant walls.


Southampton Town Quay.

Design of reinforced concrete jetty on tubular steel piles.


IBM Portsmouth.

Design of foundations for high mast lighting columns.


Singapore Metro Extension.

Tender design of temporary retaining walls to support station excavations up to 17m deep for Benaim Group.


Hillingdon Station, London

Re-design of permanent reinforced concrete pile caps to suit bored piles that had been installed out of position. Design of a steel king pile cofferdam to retain a deep excavation and to support a temporary railway deck structure. This work was carried out in association with other consultants for Balfour Beatty Civil Engineering and Stent Foundations.

Ellis Design Associates (Engineering) Ltd. Registered in the UK at: Empress heights College Street Southampton SO14 3LA Reg. No. 05595063Tel. +44 (0)1329 826434