Croft Structural Engineers completed a project in Marylebone, London. Oldbury Place was a complex project converting an existing Victorian industrial building into three modern townhouses and incorporating a new two-storey basement under the full premises.
The tight site shape and closeness of the surrounding buildings meant the design of basement works was complicated. Croft’s expertise in temporary works enabled the permanent structural design to be combined with that of the temporary works design. This allowed the client to get a great head start on planning construction works as well as countering any party wall issues.
The construction sequence was particularly tight and to achieve the programme it was not possible to construct the basement and then the upper floors, they had to be undertaken at the same time. To achieve this Croft designed a top down construction. This is a technique that is used on larger new build office developments. Croft took the technique and developed it to an existing property.
Piles were drilled and into the wet concrete steel plunge columns were inserted. From the plunge columns the ground floor deck was constructed. This allowed the superstructure works to continue while the basement works continued in sequence. This significantly reduced the construction time. Part of the basement was constructed under the road. This required Highways temporary works .
Croft has the capability to design both temporary works and permanent works. The incorporation of both elements drastically reduced the construction time and costs.
Read more about the project here.