HMP Millsike - Custodial Completion

With HMP Millsike’s structural construction completed, PCE’s HybriDfMA approach to prison design and build has yet again proved to be the blueprint for success.

Appointed by lead contractor, Kier, PCE Ltd were appointed superstructure and façade delivery partner for HMP Millsike, a category C prison that will provide places for around 1,500 prisoners. HMP Millsike is the third instalment of the New Prison Programme (NPP), led by the Ministry of Justice (MoJ).

Having been used to deliver HMP Five Wells and HMP Fosse Way, PCE’s HybriDfMA Secure Prison system has been implemented to successfully complete the structural solution for HMP Millsike. The system’s standardisation and repeatability create a platform solution to secure and modern prison build that creates certainty of cost, programme, and outcome. It ensures quality solutions that are delivered at speed and scale, whilst ensuring compliance with NOMS (National Offender Management Service) and Home Office design guides.

Design

With a track record of delivering over 10,000 secure cells, PCE has optimized design features of the Secure Prison system through continuous innovation and refinement. Part of this journey involves seeking design innovation, examining structural connections, element interfaces, methodologies of build, fabrication processes, and health and safety implications. This insight feeds into the value engineering behind the system’s ‘kit of parts’, a series of standardised components, common connection principles, and hybrid material flexibility.

PCE’s Secure Prison system’s ‘Kit of Parts’ used for HMP Millsike includes sandwich panels, internal walls, circular columns, square columns, floor units, parapet walls, ground beams, steel composite beams, and stair and landing units. These units are comprised of a hybrid of reinforced concrete and steel, creating a true hybrid superstructure. Throughout the design phase, M&E integrations were diligently coordinated within components through detailed model coordination. Clash detection then helped identify and resolve any issues early on, ensuring components issued for manufacture were of the highest quality and accuracy.

Manufacture

PCE's supply chain model offers flexibility in selecting the best offsite specialist for each project. For HMP Millsike, nine specialist offsite manufacturers were chosen from across the UK and Europe, based on required structural integrity, embodied carbon, and performance characteristics. PCE collaborated with Kier, the MoJ, and supply chain members to define and agree on quality standards, aesthetics, and tolerances, setting benchmarks for all manufacturing.

After approval of sample panels, production started on nearly 13,000 hybrid components, totaling over 50,000 tonnes of steel and concrete. To ensure a comprehensive manufacturing strategy, circa 50,000 free issues castings were integrated during offsite production, with coordination of M&E during design ensuring efficiency throughout manufacturing. Free issue castings included windows, door frames, under floor heating mats, casting conduits, Halfen channel, shower heads, and shower gullies. To ensure only the highest degrees of accuracy and precision, PCE created bespoke moulds for the duct walls, corridor walls, and cell floor units.

PCE's extensive offsite approach ensures top-quality components arrive ready for installation. Most concrete finishes are produced to accept a directly painted finish, reducing the need for plasterboard and limiting material usage, resulting in an attractive and environmentally friendly outcome.

Assembly

PCE’s structural solution was completed 25% faster than the target period. Its systemised offsite model sees a significant amount of construction activity completed offsite. This means site activity is significantly reduced, with less deliveries, less disruption, and less onsite operatives.

It is not just the steps taken offsite that add value across assembly. PCE’s standardised construction procedures, coupled with its ‘smart connectivity’ enabled PCE to assemble with pace and precision; each houseblock was structurally complete in 12 weeks. Each houseblock crew was comprised of 13 operatives including erectors, grouters, and finishers, providing a turnkey assembly solution. At its peak, the site team comprised of up to 70 operatives assembling up to 100 tonnes of hybrid material per day. Speed was not at the expense of safety, with the team recording 200,000 RIDDOR-free hours whilst assembling 13,000 hybrid components, covering 60,000 square footage of façade and floorplate.

Logistics

Navigating the complexities of a large-scale project with a diverse supply chain is challenging. By implementing state-of-the-art digital capabilities, PCE achieved precise project coordination, collaboration, and logistics. Using Ynomia, a digital asset tracking and information management tool, provided high visibility and real-time transparency, enabling informed decisions and controlled coordination. This ensured efficient collaboration across design, manufacture, and assembly, benefiting from just-in-time delivery. Ynomia's use saved over 5,000 hours and £300,000, with substantial cost savings projected for the NPP.

Social Values

Beyond delivering high-quality projects, PCE focuses on community impact. In line with social responsibilities, the project team donated technology to Stamford Bridge Gardening Club and equipment to the local youth football team. PCE supported rehabilitation by employing ROTL (Release on Temporary Licence) prisoners, who learn valuable construction and transferable skills, boosting their confidence and preparing them for careers post-release. This effort aligns with the Ministry of Justice's goals to reduce reoffending.

Summary

Through a combination of experience, continuous improvement, and a platform approach to prison build, PCE has once again been successful in the implementation of its Secure Prison HybriDfMA system. With assurance and predictability across all phases of design, manufacture, and installation, PCE’s Secure Prison DfMA system ensures safety, speed, and scale whilst adhering to the highest standards of quality and compliance.