A topping out ceremony involving the laying of a miniscule concrete slab by the secretary of state for transport has been held to celebrate the completion of the structure of the new terminal 5 building at Heathrow. The slab was inserted into the departures floor, 20 metres above ground level.

The 4.2 billion project for the airports 5th terminal is on time and on budget - after almost 3 years of work.the 6,000-strong workforce has transformed an old sewage works, previously sited at the western end of Heathrow, into a gleaming modern structure covering an area the size of 50 football pitches.

The new terminal is set to open for business at 4.00 in the morning on 30 March 2008.

Topping out ceremonies are a tradition in the construction industry and usually take place when the final steel joist is in position or when the building reaches its full height.