The architect of the proposed £475m National Stadium at Wembley this week hit back at criticism from culture secretary Chris Smith, who has said its design was unfit to host the Olympics. On Tuesday, the World Stadium Team, which includes Foster and Partners and HOK+Lobb, issued a rebuttal of the criticisms, which were based on a report by US sports architect Ellerbe Beckett.

Lord Foster told Building: “We refute it totally. The report is seriously flawed and full of inaccuracies. It quotes spurious sources, is misleading and shot full of holes.”

In a statement to the House of Commons last Wednesday, Smith said the Ellerbe Beckett review confirmed sports minister Kate Hoey’s fears that the stadium was not suitable to host the Olympic Games. Smith added that he had given developer Wembley National Stadium and Sport England until

15 December to come up with solutions to the alleged design faults revealed by the report. Otherwise, the project’s lottery grant would be reconsidered.

It is understood that Smith has urged the architects to reconsider the proposal for retractable seating over a permanent running track. The current design is for a temporary track be built on a concrete platform over the pitch. The team was due to present its response on Thursday to officials from Sport England, UK Sport, UK Athletics and the British Olympic Association.

HOK+Lobb senior vice-president Rod Sheard claimed there were serious errors in the report, which was completed to a brief from UK Sport. The review compared the National Stadium’s merits as an athletics venue with others, such as the Sydney Olympic Stadium.

But Sheard noted that Ellerbe Beckett failed to provide information on the Olympic stadium in Athens and the Stade de France, which are designed to stage athletics events and football matches. Instead, said Sheard, it only drew comparisons with purpose-built Olympic stadia.

Ellerbe Beckett director Peter Barrans attributed this to shortage of time. He said: “We could not get information from the architects of the Stade de France in time.” He acknowledged that they did not try to obtain information about Athens.

Barrans denied coming under political pressure to find fault with the design. He said: “We were asked to carry out an audit of the design and raised issues that we could see were not fully resolved.

Factual errors in the report included a wrongly labelled diagram of the Sydney Olympic stadium. It also contradicts itself over Olympic seating standards. It is understood that the World Stadium Team will again reject the idea of retractable seating because of the £57m capital cost, the delay to the planning application, high maintenance costs and diminished sight lines for football spectators.

It insists that building a concrete platform is feasible and not as disruptive as claimed.

A design team spokeman said: “We’d build the platform over the winter months. We’d hold the athletics meeting in the middle of the year, we’d have the football pitch operating with a 68 000 capacity for the cup final and the iernationals. At the end of that year, we would take the running track out.

“The International Olympic Committee does not necessarily need the stadium ready in Olympic mode a year ahead. It wants to know the toilets flush and that people can get to their seats.”

The World Stadium Team presented the designs to the Commission for Architecture and the Built Environment on Wednesday. CABE will issue their response later this month.

There was also speculation that the row may result in Wembley becoming a purely football and rugby venue while other sites were developed to host athletics events.

The Ellerbe Beckett report said

The east-west orientation of the home straight means runners and spectators would be staring into the sun. Only three lanes of the track will be covered by the north roof, so some runners may have a dry track and others wet. The International Olympic Committee wants the stadium finished a year ahead of the Olympic Games. This could render the stadium unusable for international football for upwards of two years. Sight lines and legroom would be compromised by the extra rake of seating in Olympics mode.

The Wembley team responds

By 3-4 pm, the sun goes behind the 40 m high stadium roof, and anyway the runners are looking down. The IAAF is happy with the roof. The roof is 40 m high. Rain does not fall in a vertical line for 40 m, so some lanes would not be wet and others dry. The conversion would take six months. However, only one or two football matches would be missed if the work was done in winter. The IOC wants the stadium finished a year in advance, but not necessarily in Olympics mode. Legroom will be better than the Stade de France and sight lines at least as good .

Countdown to Wembley clash

29 July 1999 Launch of first design, featuring four 153 m long masts 6 Oct 1999 Wembley National Stadium Limited, at the behest of Chris Smith, presents scheme to British Olympic Association for comment 19 Oct 1999 Kate Hoey calls meeting of all interested parties (WNSL, World Stadium Team, Sport England, UK Sport, UK Athletics, BOA) to discuss concerns over proposed methods of converting stadium to athletics mode Nov 1999 UK Sport commissions Ellerbe Beckett to carry out independent review of the design, to check suitability for hosting world class athletics 15 Nov 1999 Final design, featuring 133 m high arch, submitted to Brent council for planning permission 29 Nov 1999 UK Sport delivers Ellerbe Beckett report 1 Dec 1999 2.15pm All parties (see above) summoned to meeting with culture secretary Chris Smith to read Ellerbe Beckett report 3.30pm Smith tells House of Commons the new stadium design is unfit to host Olympics. He gives architects until 15 December to propose solution