黑洞社区

For anyone passing through White City in west London, it is hard to avoid the new shopping centre under construction. Westfield London is currently a vast site of frenzied activity as workers race to complete five anchor stores, 265 speciality shops, 40 restaurants and leisure facilities. Lorries queue up along the ramp off the motorway to feed the 14 tower cranes that are keeping the project moving.

The 45-acre scheme also includes a new tube station and bus interchange at Shepherd鈥檚 Bush, a station for the West London overground line, a new station on the Hammersmith and City line and another bus interchange near the BBC headquarters at White City. It is hoped that the 拢1.6bn scheme will attract customers from across Greater London, anxious to part with about 拢5bn a year. But first, developer Westfield has to get the project finished.

黑洞社区 anything on this scale is a major challenge, but this project has had more than its share of ups and downs. Originally it was being developed by Chelsfield to a plan drawn up in the nineties by Ian Ritchie Architects. Contractor Multiplex had been engaged to do the job and was on site when Australian developer Westfield bought out Chelsfield in December 2004.

This is where things start to get complicated. Westfield had its own ideas about what makes a successful 鈥渓ifestyle destination鈥� and wanted to change the design. To complicate matters further, Westfield likes to do everything in-house, from design right through to construction. As Iain Johnstone, the company鈥檚 development director, puts it: 鈥淪elf-sufficiency has been our model for the past 30 or 40 years. This makes us responsive to changes in the marketplace and more efficient and improves results.鈥� Having a separate contractor didn鈥檛 fit this vision, so it had to find a way to get rid of Multiplex and take over the scheme鈥檚 construction itself.

And as if that wasn鈥檛 enough, there was also the small matter of a huge Central line depot taking up a third of the site. The plan was to build a replacement depot underground then build over the old one, but complications had put this behind schedule and were threatening to delay the whole project.

So, with the project already showing itself to be a huge, unwieldy beast, the first question is, why on earth didn鈥檛 Westfield just leave things as they were? Johnstone says the company always looks carefully at each development to see what it will get out of it, how it is positioned in the market and what will make it appealing to tenants. Get this right and the customers will follow. When it applied this exercise to the original White City designs, it found the scheme didn鈥檛 meet its standards. Retail design had moved on since the nineties and the centre would have to compete with established shopping areas nearby. 鈥淥xford Street shops are quite large,鈥� says Johnstone. 鈥淲e needed to provide a similar offer to attract tenants.鈥�

Westfield decided to make some big changes. These included inserting a mezzanine floor to create a bigger retail area and changing the roof material from ethylene-tetrafluoroethylene to a more appealing glass covering and adding green roofs over some of the unglazed areas to increase biodiversity. Full air-conditioning was introduced, the position of the malls was tweaked and Westfield ditched most of the lifts in favour of escalators, which affected the design of the core and necessitated big apertures in the floorplates. The developer also wanted to change the structure from concrete to steel as it believed this would be more flexible should retailers鈥� needs change.

The next step was to remove Multiplex. The trouble was that the contractor was already on site building the original scheme when Westfield took over. It had done the piling and procured 65% of the packages. How did Westfield cope with such a major change?

The answer was simple 鈥� it took on the Multiplex employees as Westfield employees. 鈥淭his enabled us to have continuity and maintain the programme,鈥� says Keith Whitmore, Westfield鈥檚 director of construction. He says nearly all of the 70-plus Multiplex employees on the project chose to move to Westfield. This helped the developer build up its construction resources for the future. And there was another advantage: 鈥淚 think I am one of the luckiest construction directors in the industry as I don鈥檛 have battles with the contractor,鈥� says Whitmore.

Westfield took over the job in August 2006 and it seems to have been an amicable and smooth transition. Johnstone claims Multiplex accepted that Westfield did things its own way. Flan McNamara, a former Multiplex employee who is now Westfield London鈥檚 construction director, agrees: 鈥淚t suited Multiplex as it was withdrawing from construction in the UK.鈥�

But the minute the site was under Westfield鈥檚 control it had the problem of the tube train depot to resolve. Multiplex had been building a 拢70m, underground 16-train depot to the west of the site. The idea had been for London Underground (LU) to take this over, thus releasing the pre-existing depot, which was slap-bang in the middle of the site, for redevelopment.

The new depot should have been handed over to LU as Westfield walked through the door, but it was not finished yet. 鈥淯ntil we had finished and handed it over, LU wouldn鈥檛 release the ground above it,鈥� says Whitmore.

黑洞社区 the depot was always going to be a big undertaking: its scale, the fact the Central line had to be diverted to connect to the box and the difficulties of working next to a live railway, were all obstacles to overcome. And when there were problems on the Central line that caused trains to be diverted into the old depot, LU took back possession of the areas next to it without any notice.

When Westfield took over, all the heavy work had been done, but the fit-out was still under way. 鈥淲e took on the challenge to deliver this by Christmas,鈥� says Whitmore.

This challenge was all the greater because LU was a very fussy client. Whitmore cites as an example the safety gates that drivers use once the train has been parked. 鈥淵ou wouldn鈥檛 believe the dialogue we had over these gates,鈥� Whitmore says. 鈥淪hould they be single gates or double gates? Would the drivers be able to locate the gates?鈥� He adds that LU wanted to change the mesh platform surfaces after they were completed, because drivers might drop their keys through them. Fortunately, as mesh was in the original specification, it stayed.

鈥淲e piled an enormous amount of time and effort into handing over on time,鈥� says Whitmore. This included working longer hours when necessary, which vindicated the self-sufficient approach. 鈥淏ecoming part of the client body rather than just being the contractor was one of the real winners,鈥� says McNamara. 鈥淚f I was the contractor I鈥檇 have had to go through a project manager who鈥檇 then go back to the client. Now I had the authority to just do it.鈥�

Whitmore hit his target and was ready to hand over the depot just after Christmas 2006. 鈥淚t was a milestone in the project 鈥� we were chomping at the bit,鈥� he says.

While the depot was being sorted out, Westfield was planning the buildings to be built on the 鈥淏lue Lands鈥�, the nickname for the site of the old depot. These were some of the structures that, for speed of construction and greater flexibility, Westfield wanted to switch to steel. It had started the redesign work the day it took over from Multiplex and the steel was fabricated while the depot was being sorted out, allowing work to start the day LU handed the site over.

Westfield also reviewed the programme to see if it could be tightened up. 鈥淭here is always something you can improve,鈥� says Whitmore.

A good example of this was the tiling in the malls. The original plan was to complete the roof then tile the floors. Instead, the roofing scaffold has been designed so the tiling team can work underneath it and set out the floors 鈥� once the scaffolding moves onto the next section, the tiles are laid. 鈥淲e鈥檝e saved 20 weeks on that part of the programme,鈥� says Whitmore.

Other changes to the design were also accommodated without much difficulty. 鈥淭he clever bit was to incorporate these changes into the existing design, as all the piles were in place,鈥� says McNamara. The piles were able to take the additional weight of the structure but the structural columns were now in the wrong place. This was solved by using transfer structures in the underground car park to switch loads to the new locations 鈥� all done without losing any parking spaces.

Now Westfield has resolved the design problems, it is cracking on with the job. It has taken full control of the cranes rather than leaving them in the hands of specialists so it can control the movement of materials. Piling and the cores are complete on the Blue Lands and the steelwork is pressing ahead 鈥� at the moment, there are 12 deliveries of steel a day.

Whitmore says the overall programme is on track to be finished by the end of next year 鈥� any areas that have slipped are balanced by others that are ahead. Which will be music to the ears of the shopaholics of west London 鈥�