Final cost will be higher than the £326.5m agreed by sole contractor Multiplex, but still 'value for money'.
Wembley stadium will cost £410m to build, it emerged this week.

The construction cost has been widely reported as £326.5m because that was the guaranteed maximum price fixed between sole contractor Multiplex and client Wembley National Stadium Limited in September 2000.

But Building has learned that the figure will be £83.5m greater than that. Project insiders claim that the bulk of the cost of the lump sum design-and-build contract will be made up of £380m of trade packages. This includes steel, concrete, building services and preliminaries, and it allows for inflation up to the end of the project. The rest of the cost will include £10m for demolition, £10m for fixtures and fittings and a £10m contingency.

It is understood that Multiplex will be allowed to keep any money it saves during construction.

The £326.5m figure did not include fees, interest or fixtures and fittings. It did include a hotel and offices which have since been removed but not the newly enhanced banqueting facilities.

One source said: "The prelims have gone up a bit – that's the result of all the faffing about on this contract in the past two years. The trade package was always going to be around the £350m mark. People are saying that Multiplex has driven up the costs, but that's just not the case. The contract is extremely robust in terms of cost."

Even £410m is considerably less than the £498m quoted in a report by QS Cyril Sweett, published last week. The report said £498m – a figure which included £48m for banking and £40m for insurance and design fees – was good value. "We consider that the Multiplex bid is value for money in terms of the market price for the scheme as designed, and in comparison with stadiums of similar standing."

Wembley will be more expensive than Stade de France and Stadium Australia in terms of the cost per seat but cheaper in terms of floor area, said the report. However, the pricetag of £498m is based on a construction start date of 1 May, and this has been put back to late summer.

Of Multiplex, the report said: "[It] is a major contractor with substantial international experience. It is, however, entering a high risk transfer contract in the UK, which is a new market."

WestLB was today due to sign a mandate to back the project after concluding a heads of terms agreement with WNSL at the start of the month. Financial close is due in August.