Haden Young uses innovative modular technique for new Stoke Mandeville wing

- Asta Powerproject enables build of new acute facility

Stoke Mandeville is a renowned hospital in Aylesbury, Buckinghamshire and, as part of the Government’s PFI procurement plans, a new acute block has just been completed - including 10 wards, two operating theatres and 234 beds. Working with its joint venture building partner, Alfred McAlpine, Haden Young designed and installed all electrical and mechanical building services - a contract worth over £12 million - using Asta Powerproject for the crucial planning functions which took place over a four month period.

For this project, Haden Young used an innovative modular manufacturing process where corridor services distribution modules were constructed off-site in six-metre sections – to increase speed, improve quality, use manpower more efficiently and reduce health and safety issues.

Haden Young provides expertise in mechanical and electrical building services for high profile clients, within budget and on time. The planning functions for projects are completed using Asta Powerproject. The Stoke Mandeville contract required detailed planning to ensure both off-site and on-site activity was carefully coordinated to maximise the benefits available from this innovative construction method. As there were so many activities to be delivered within the four month process, Haden Young planned them down to great detail - to single day activities where necessary.

Jon Hall, project manager at Haden Young, comments: “Asta Powerproject enabled us to look at the short term and overall picture together. Firstly, top level planning showed the outline progress of each discipline. Each one could then be broken down into summary bars to give us the short term view, for example to show us what was happening each day.”

The hospital wing, a new build on a brownfield site, interconnects with the existing hospital at both ends. Amongst the services Haden Young commissioned in this complex project were ventilation, heating, lighting, drainage, medical gases pneumatic tube delivery system, high voltage system and steam boiler plant. As the existing hospital services had to be kept running, there needed to be minimal interruption to clinical services.

Haden Young’s manufacturing process for the six-metre corridor services sections made use of frames supporting ducts, pipes and electrical containment. Built to 1mm tolerance, the sections were delivered on a flatbed truck, lined up with lasers and bolted together on-site. Installing up to four each day, the 300 sections took less than four months to complete – which included constructing the outer shell building.

There are many benefits to using this modular process, not least increased efficiency and productivity (i.e. speed of manufacture). In addition, quality of workmanship, the fact that off-site build can start way before on-site build if required, reduced on-site manpower requirements (e.g. no need to weld onsite and all lifting is mechanical, rather than manual) and the associated reduction in on-site health and safety issues.

As the modular system involved working in a more controlled environment, rather than the ever-changing environment onsite, the planning was key to project control. It meant that more planning was required up front for the off-site manufacturing work, and less time was required actually constructing the corridors on site.

Hall explains: “As this was a bit different to more traditional construction projects, the planning and resourcing were also different and needed to be more defined. Normally, you would plan deliveries onsite from every discipline, which means coordinating up to 10 teams, however with the modular system most work is carried out in the factory. Asta Powerproject is an integral planning/resourcing element and proves it is flexible enough to cope with different construction processes.”

Increased efficiency and productivity is a key objective for any business and one of the main ways this is achieved is through operatives working in a factory environment at table level, installing side by side, rather than high up on scaffolding and outside. In addition, only 60% of the workforce was required onsite – compare this to more traditional methods which could easily see 50 contractors working on steelwork, pouring concrete, cladding etc. Also normally the weather can affect timing onsite significantly, however moving critical elements to a factory build gave the Joint Venture more control.

Overall, Haden Young found Asta Powerproject to be ideal for planning/re-planning and managing of resourcing and productivity levels – and as they could see a snapshot of onsite progress, it provided a powerful summary tool of the whole build for client reporting. They used progress drop downs each week, in addition to higher level summary programmes.

While the company found the software to be flexible and comprehensive, some users did call Asta’s support team to solve any issues: “Asta provides a good technical support service, I’d give them at least nine out of ten for help. Their experience in this sector is apparent - what was particularly useful was the fact that they understood what we were trying to achieve,” says Jon Hall.

Overcoming problems
As with any construction project, it is an ever-changing environment and contingencies need to be in place. As a planning tool, Asta Powerproject can be used to great effect to highlight and overcome problems. “If the sequence of events are programmed in properly – the cause and effect of potential problems can be adjusted all the way to deadline date. We can test for numerous ‘what if’ scenarios and clearly see the effect on the end date and any subsequent re-scheduling required,” says Jon Hall.

As the operation of the hospital had to come first, the diversions/interface with the existing hospital services created a major logistical challenge. For example, the high voltage ring main around the site had to be diverted. As the power supply had to be disabled, this required detailed planning and close liaison with the Hospital Trust and facilities managers. “Disabling the power supply had to be postponed a few times due to clinical restrictions, however we understand that clinical procedures need to take priority in a busy hospital,” adds Jon Hall.

Haden Young is particularly proud of the result. The new acute facility for Stoke Mandeville, mainly for spinal patients, is important to the local community and the company are very pleased to have received a great deal of positive feedback from locals.