The best medicine

“It’s just like a giant Meccano set,” says Jason Cummins, one of 12 construction managers working on NG Bailey’s ambitious St Helens and Knowsley Hospital programme.

In fact, Meccano is probably a damn sight harder to fathom than the huge modular units that make up much of the m&e installation at Whiston Hospital, one part of this massive Merseyside NHS development.

Parts are carefully labelled so that engineers know precisely where they fit into the overall grand picture on site.

“Every module is given a reference in the factory, and we then have a set of drawings with all the positioning on,” explains Chris Bailey, marketing manager for Bailey Teswaine.

The flagship PFI scheme will in fact deliver two state-of-the-art units for the NHS Trust – the second is St Helens Hospital.

The NewHospitals Consortium, comprising Taylor Woodrow Construction and Innisfree, has been chosen as a private sector partner. NG Bailey is working alongside Taylor Woodrow, which has taken on the design and construction of the new facilities.

A challenging £350 million building programme brings together three of NG Bailey’s specialist divisions: Bailey Building Services, IT arm Bailey Teswaine and Bailey Offsite.

The group’s target is to make up 25% of the project value through offsite construction.

NG Bailey has been involved in the project since the very early design stages, and this has undoubtedly reaped major benefits. Unlike a traditional build, there are no walls in place during the m&e fit-out. Instead there are just markers to indicate where the walls will be inserted at a later date.

This means that the huge modular units can be lifted in with the minimum of problems.

“The architects were very sceptical about us being involved so early on. But they went to look at our offsite facility, realised how much benefit this approach could bring and finally bought into it,” says Bailey.

“That sort of thing happens quite often – it requires a change of attitude. Unfortunately, changing the way the industry views off-site construction is not going to happen overnight.”

The original Whiston Hospital is set to be completely transformed, with 75 000 m2 of new-build and a further 12 000 m2 of refurbishment.

At six storeys high, the 963-bed acute centre will be among the largest hospitals in the UK.

A 25 000 m2 diagnostic treatment centre at St Helens forms the second part of the Merseyside programme.

Up to speed

The m&e team commenced installation at Whiston Hospital in March 2007. The vast project is due to be completed by February 2010.

“At the installation stage, it’s a very tight programme, and there’s no room for error, but that’s where being in there from the very early design stages comes in,” says Cummins.

“We were actually looking at the process for four years before we actually started on the project.”

With the assistance of offsite specialist Panaloc, in excess of 3000 service modules have been built at NG Bailey’s prefab facility in Bradford, to a value of £6 million. This includes 800 bathroom, shower room and WC pods.

When the plug-and-play pods are delivered to the site, there are just three connections for the m&e team to take care of.

“We have about 15 different types of bathroom in total, so you’ve got all of those varying washbasins and different types of kit. It takes time when you’re using more standard methods,” says Cummins.

“Plus you also get a fair bit of damage caused by others on site when they’re installed traditionally. When they’re brought in as lockable units, you stand a better chance of things not getting smashed.”

The pace of the installation is impressive. All the Apex modular wiring, nurse-call circuits, medical gas installation and above-ceiling work was completed within just eight weeks during the first visit by fit-out experts.

In Cummins’ estimation, the project would have taken around eight years, had traditional installation techniques been used.

“Offsite, they make one of these modules up in a couple of days. If we’d done this on site, it would have taken us four to five days.”

Time team

Time savings are particularly important on hospital projects, as Cummins points out. “The problem with hospitals is that the design is forever changing. In office complexes, a design freeze will happen, but in theatres, new kit will always be coming out.

“For instance, on hospital projects we always leave the MRI suites until last. But you never get an extension with regards to time that’s my concern about design alterations.”

Adopting an off-site manufacturing approach also results in colossal gains when it comes to health and safety practice.

“The modules are being put together on work benches as opposed to up on scaffolds. I would say that’s the biggest impact off-site manufacturing has – just reducing the sheer numbers of people on a building site and all the safety risks associated with that,” says operations manager Ken Dickinson.

NG Bailey is also using electric lifting machines called straddle stackers to raise the multi-service modules up into position. This reduces manual labour, which helps in terms of back injuries and strains.

“By simply pulling a lever, one person can lift the whole module up on his own. We’re talking modules that are 6 m long by 2 m and 1 m deep.

In the past, you actually had to rely on about three or four guys, all at different positions, with mini hoists, manually lifting one corner up at a time,” explains Dickinson.

“It’s a long, drawn-out process. Now it can be done in minutes as opposed to half an hour. We ended up using it for other things as well, like ducting and pipework.”

Plug and play

Main switchrooms were delivered as composite package substations, including medium-voltage switchgear, transformers and low-voltage switchpanels, which were combined as one assembly.

These units incorporate all relevant controls and meters, ready to export information on the buildings’ energy usage into the overall building management system.

Pre-assembled, prewired and factory-connected section boards and final distribution boards provided major savings on construction time, with experienced electricians no longer lost in the distribution cupboards for weeks on end.

A true plug-and-socket interface between distribution boards and field wiring was introduced.

Dual-circuit distribution boards were delivered to the site, complete with emergency supply changeover facilities. These were fully populated with protective devices ready terminated, metering in place and prewired for direct connection onto the BMS system.

All home-run circuits emanating from the distribution boards were fully prepared offsite, with both ends terminated and labelled.

The source point plugs directly into the distribution boards via non-interchangeable arrangements.

Apex modular wiring systems have been used throughout the development to provide final circuitry to power outlets and luminaires.

“What you’d usually get is just a mass of wires,” says Cummins. “All these cables are like spaghetti junction. You normally find an electrician in here for weeks trying to connect them all up.

“With this new Apex system, it’s already pre-installed, so you just plug them in. Timewise, it’s unbelievable how much we’re gaining.”

Luminaires are pre-flexed and connected, not only with the supply cabling, but also with emergency test monitoring data cables, and delivered to site lamped and packaged, ready to be plugged in and lit.

Mechanical aspects of the project are also largely carried out offsite.

“Because of the sheer size of the prefabricated ventilation plants, they’re delivered on the back of lorries and craned in, and then the air-handling units are just bolted together,” explains Cummins.

“All in all, it has taken the thinking out of the fit-out.”

So the benefits of offsite modular construction include enormous reductions when it comes to installation times, onsite costs and safety risks, teamed with a significant increase in quality. Various other benefits include negligible onsite waste and far less disruption to neighbours.

Are there actually any downsides to prefabricated installation?

Not for NG Bailey perhaps, but Taylor Woodrow encountered a rather surprising objection, having adopted an offsite approach to the facade.

“The complaint was that the bricks looked too perfect,” laughs Cummins. “They’re actually having to rough them up a bit.” Some people are never satisfied.