Stars and strife

It would be fair to say that Sir John Tiltman has come up against a few unscrupulous operators in his time. "Either you get a contractor who is there to try and minimise claims. Or they make the situation worse. Many lump sum contractors are the latter," he says.

Tiltman is far too discreet to name names. But his experiences have left him with a negative attitude towards lump sum contracting. Conversely, his projects under construction management have been happy ones. Most recently he oversaw the refurbishment of Clarence House for Charles and Camilla following the Queen Mother's death.

When Tiltman took on the lead role for Greenwich Maritime Museum"s new planetarium project, having just retired from heading up the Royal Household's property division, the museum had planned to go down the lump sum route. He offered construction management as an alternative and won them round.

Tiltman's reason for choosing CM was control. "You have a say in which subcontractor is selected rather than the main contractor choosing the cheapest," he says. But with myriad difficulties that have beset this project, CM has proved its worth because of its flexibility, according to construction manager, Kevin Martindale of Gardiner and Theobald Construction Management (GTCM).

Tiltman and Martindale worked together on Clarence House and the restoration of Windsor Castle after the fire. Was Martindale a key factor in GTCM winning this one? "You judge [the tender] in part on the quality of the construction manager who will be in charge of the project on site," says Tiltman. "You take references and find out how they did on their last job."

Potential claims

There have been enough changes, delays and potential claims situations on this job to turn most construction managers' hair grey. But Martindale is bursting with positivity. "It's great fun: so unusual, so interesting," he says with an enthusiasm which feels very genuine.

Alarm bells started ringing when Tiltman joined the client team and discovered that the planetarium equipment had yet to be selected, which spelt potential disaster as the choice has a knock-on effect on several packages. "We have held back building little elements of the building until we know what's going on," says Martindale. The choice of equipment, which will be only the second laser projector of its type to be installed in the world, was made in July.

Martindale's construction management style is hands on, which he says allows him, together with his supervisors, to assess fairly how much a trade contractor should be charging to come back and finish things off. "The metalwork for the walkway has only just been delivered because they had not decided on the equipment," he says as we tour the site.

"You can allow for that without taking the client to the cleaners."

The problem of the late specification of the projector fades into insignificance when Martindale explains the issues relating to the bronze funnel which will house the 120-seat planetarium. Protruding from the ground like some part of a large scientific instrument, this architectural flight of fancy has brought challenges at every stage. Truncated top and bottom at strange angles aligning to celestial bodies, one side slopes at 55% to the horizontal.

"There's no easy way to get to the surface. Even building a scaffold around it was immensely difficult, slow and expensive. It has been very tricky to build," says Martindale.

When asked if he has cursed the architect, Martindale gives a wry smile. " We all curse them, because of all the problems we have. But who wants to build another Tesco?"

Then there was the small matter of finding a firm to supply the bronze. The PQS had taken pricing advice from a company which turned out to be a steel specialist and in the end declined to tender. Prices came in up to six times over budget.

Martindale and the other project players re-examined potential solutions and retendered. "We cut and shuffled the programme to enable the project to continue," says Martindale. "And because it is construction management, we were able to minimise cost implications."

Responsive Engineering, a precision engineering firm, finally won the tender, but it was still over budget. Some money came from the contingency and from trimming "nice-to-haves" from lighting and building services. Then another £400,000 had to come from donations, which have funded the whole project.

Before the bronze even arrived on site, construction of the cone was running 16 weeks late. It took 22 weeks instead of six. Engineer Cameron Taylor had opted for spraying concrete onto a mesh to create the unusual shape, having examined many options.

"They were trying to spray to very fine tolerances. But spraying is quite a robust process," says Martindale.

What would have worked better? "We have all stood there and said 'this is not the way to do it', but there is not an easy solution," admits Martindale, before offering precasting as a potential one. But he adds that this may have proved difficult to fabricate and very expensive.

Once built, a survey revealed that the cone was not quite as designed. "If that had been a main contract it would have been a nightmare," says Martindale. Instead he worked with Responsive Engineering on a best fit exercise.

To do the job, Responsive Engineering had to develop special welding techniques. "No one has ever done this before with this type of engineering," says Martindale. Because bronze moves so much under heat, the edge of each sheet has to be preset with a curl at the edge. These are created by welding steel rails onto the bronze sheets near the edges, and attaching a device to the rails once in place to curve the bronze. The idea is that as the bronze is heated, the sheets deform to form a smooth surface.

we curse the architect because of the problems we have, but who wants to build another tesco?

kevin martindale, GTMC

The hot summer, however, wreaked havoc on the careful calculations. The eight welders from Responsive Engineering had to cut out some of the welds and adapt the technique to cope.

Martindale is relaxed about the delays this could cause. "If the bronze goes on longer and delays paving around the edge, we can leave one man here with a desk and a chair inside the building while the paving is going on. Potential costs from a main contract due to the bronze cone would have been very substantial."

Thank goodness, with all those difficulties on the new build element of the job, that the refurbishment of the Victorian building, which will house a museum and conference rooms, was straightforward.

Or was it? Because the interior was last done in the 1960s, the cruciform building was gutted. Nice and easy. But then the design required the contractors to shoehorn a clinical modern museum interior into a Victorian building that knows no right angles.

"Allies & Morrison's design is very precise and exacting and not very forgiving in the details they have come up with," says Martindale. "Adapting them to fit the building that allows the shape and size predicted is quite tricky."

"There are also heavy services and distribution of the services around the building has proved very difficult. We are constantly juggling the design of the joinery and fitted furniture."

Here again, a hands-on approach is best says Martindale: "We tend to get involved. The site supervisor and foremen get stuck in. They tend to be there with the chippies, come up with a solution and get on to the architects. Because of that, we know what's going on."

Joint decisions

When Martindale describes how construction management works, it all sounds very cuddly and enjoyable, construction manager and designers sitting down together to take joint decisions. First, they agree the work packages. There is an art to this, determined by the programme and the market place. On this job, time concerns prompted the decision to pull the muck away out of the ground works so they could progress that before the reinforced concrete had been finalised.

And the packages have to attract interest:

"You have got to make a package attractive. Contractors have got to want to price the job for you," says Martindale. "Gone are the days when you decided who you wanted to work for you. Now things are more equal."

The group then decides who to award subcontracts to and recommends that firm to the client. Refreshingly, Martindale does not do the whole 'price is not the most important issue at tender stage' routine.

"The economic reality is that you generally start with the lowest price and say 'is there anything wrong with this, is it good enough?' Although it might be something specialist as with the bronze where we looked for the best technical solution."

Since construction managers are paid on a fee basis - staff costs plus overheads plus profits - some argue this is a disincentive for them to get on with the job. Martindale counters this by saying that GTCM relies heavily on repeat work. Tiltman agrees: "If you had a firm that was so poor that their motive was to try and drag their feet, then you have employed the wrong people."

But it is the Scottish parliament that really damaged construction management's reputation. Putting the willies up many a public sector procurer, that project illustrated that for construction management to work, certain conditions need to be met.

Martindale, perhaps predictably, says the construction manager is the key. "You absolutely have to trust the construction manager, it's such a non-adversarial way of doing things."

Informed clients

Tiltman cites an informed client as a must: "It's vital. It would not be possible otherwise." Martindale, however, says that some clients have little input. "Some want to see everything, warts and all. Others don't want to know anything. On this job the client is quite involved because of the sheer amount of changes and alterations that have had to be made."

A robust cost plan is also key, suggests Tiltman. "The risk area is that you plunge in before you have any certainty over some of the elements. You do have the flexibility that if you overrun, you can trim things off later parts of the project, but then you are trimming bits you can see."

"We have managed to do this job without any trim. We have built the job we intended to build."

So a success story for construction management. Maybe. But Martindale and Tiltman are two of the industry's true gentlemen: experienced, respectful, competent. Put those two together under any form of contract and you could expect a winning project.