States of Jersey Police Headquarters

Arup Rothwell were appointed by Jersey Property Holdings as Project Structural and Civil Engineers for the construction of the new States of Jersey Police Headquarters.

The project included the construction of a new build four storey plus basement building on a constrained site at the South East of St Helier.

The new building was placed on the site of an existing public car park and in order to replace the lost parking area, a secondary project was to extend the top floor of the adjacent multi-storey car park.

The headquarters building consists of a lightweight steel framed top storey over three storeys of concrete framed superstructure, a ground floor podium level with car parking in the basement under.

Infill walls are a combination of blockwork and in-situ Reinforced Concrete (RC) and floors are in-situ solid RC slabs. Foundations consist of RC ground beams and pile caps with 450mm continuous flight auger piles under.

Complications included; the requirement for the structure to resist blast loads, load transfer structures and a 4.0m tall existing retaining wall that supported a main road to the South of the site. The foundations of this wall protruded into the proposed building footprint and careful detailing was required to position the new foundations in between the existing.

The multi-storey car park extension was constructed in a lightweight steel frame with a composite metal deck floor structure.

The new car park area was designed to suit the restrictive existing floor to ceiling height. It was also detailed carefully to integrate with the existing concrete frame structure and to not affect the existing cathodic protection system.

We are pleased to report that the project was completed on time and on budget by main contractors Rok-Regal Construction.

Project Scope
• Construction of a new build four storey concrete framed building with basement parking.

Rothwells Scope
• Site attendance.
• Below ground drainage design.
• External works
• Green Street MSCP extension.

Arup Scope
• Structural and Civil Project Engineering

Client
States of Jersey Property Holdings

Architect
IBI Taylor Young