Documents seen by the BBC suggest a desire to save money was behind the switch from zinc to aluminium

Leaked documents appear to show that cheaper cladding was used on Grenfell Tower than the more expensive alternative originally specified.

Paperwork seen by the BBC suggested contractors working for Kensington & Chelsea council three years ago were asked to replace zinc cladding with a more economical aluminium version.

One document – described by the BBC as a list of requested savings sent to contractors in July 2014 – details potential savings that reduced the cost of the contract by £700,000 to £8.5 million.

It includes £293,368 that would be saved by fitting “aluminium cladding in lieu of zinc cladding”.

The BBC said that as well as altering the colour the switch was designed to save money. The broadcaster added that there is no suggestion a deliberate decision was made to cut fire safety.

Meanwhile The Times reported that an “urgent nudge email” about cladding prices was sent from Kensington & Chelsea tenant management organisation to project management consultants Artelia, in which it said: “We need good costs for Cllr Feilding-Mellen and the planner tomorrow at 8.45am!”

Rock Feilding-Mellen, deputy leader of the council and chairman of its housing committee, was overseeing the refurbishment of the 1970s 24-storey block.

Last night residents were barred from Kensington & Chelsea council’s first cabinet meeting since the Grenfell fire. Journalists were only admitted after media organisations gained a High Court order half an hour before the meeting was due to begin. The government criticised the council for its actions. The meeting was adjourned after a brief statement read out by the leader who claimed any discussion could “prejudice” the forthcoming public inquiry.

A council spokesman told the Times that the budget for the project had been £6.9 million but that it was Cllr Feilding-Mellen who had argued for increases which raised it to £10.3 million by June 2014.