A property developer has been fined £1m after a 130kg window pane fell 26 storeys from a luxury riverside development in south London, killing coach driver Mick Ferris.

Specialist façade contractor Lindner Prater was also fined £300,000 at Inner London Crown Court after both companies were found guilty of ignoring foreseeable risks. Judge Boyle ordered each firm to pay £125,000 in prosecution costs.

Two other firms involved in the project, architecture practice Foster + Partners and engineering consultants Wintech Ltd, were cleared of the same charge.

Mr Ferris, a 53-year-old father-of-two who worked for Clarkes of London, was crushed by the 20-stone glass pane on the morning of 2 October 2018 as he returned to his vehicle on Albert Embankment in Vauxhall. The glass fell from The Corniche, where luxury flats have previously been marketed for £3m.

The court heard that a window had previously fallen from the development in August 2017, but the design was not substantially altered following the incident.

In a statement read to the court, Mr Ferris's wife, Rachel Ferris, said her husband's death could have been prevented. "If somebody had done something differently – anything – it would have changed our lives. We wouldn't be in this position," she said. "The thought this could have happened to anybody is always with me. It could have been a child."

Mitigating for St James Group Ltd, Prashant Popat KC told the court the developer was "deeply remorseful and regretful", adding that Lindner Prater "should have done more to complete and document the risk assessment process".

Health and Safety Executive principal inspector James Goldfinch criticised the safety failures on site. "The fact lessons had not been learnt from a near miss the year before makes what happened on that day all the more galling," he said. "For a window to fall once was quite extraordinary, for it to fall again was simply criminal."

Following the fatal incident in 2018, tributes were paid to Mr Ferris, including by television presenter and fellow West Ham supporter James Corden, who noted at the time that he had died in the most sudden of circumstances.