Commons bosses 'disappointed' as cost of Big Ben restoration soars by nearly £19m
The cost of repairing Big Ben has soared by nearly £19 million more than previously estimated, it has emerged.
Parliamentary bosses said they are "extremely disappointed" after the discovery of additional Second World War bomb damage, asbestos and the toll of pollution increased the final bill to £79.7m - up from the most recent estimate of £61.1m
Extensive surveys on the 177-year-old structure revealed that atmospheric pollution had taken a "severe" toll on the stone used to build the Elizabeth Tower, as well as that used for later repairs.
Bomb damage inflicted during the Second World War was meanwhile "found to be more extensive than first thought", while hundreds more stone repairs than first expected will be needed to restore carvings to those in architect Charles Barry's original design.
Asbestos has also been discovered in unexpected areas of the Tower, while toxic lead paint had been used in previous restorations "to a much greater extent than anticipated", the Commons Commission said.
A specialist clockmaker has had to be drafted in to repair the tower's highly-complex timepiece because of a "complete lack of drawings for the mechanism", while additional damage to the tower has required much more regular changes to the scaffolding around the tower than had been expected.
A spokesperson for the House of Commons Commission said: "It is very frustrating to learn that the Elizabeth Tower project requires yet more funding, having agreed an extra £32m in 2017.
"We have requested more detailed information about the lessons learned from this experience – as well as assurances that more robust estimates are prepared for works of this nature in the future."
House of Commons director general Ian Ailles said restoring Elizabeth Tower "had been more complex than we could have anticipated".
He added: "With a 12m square footprint and a prime location right in the middle of a busy working Parliament, understanding the full extent of the damage to the Tower was impossible until the scaffolding was up.”
"Alongside other issues, such as the impact of often inappropriate conservation methods used by our predecessors, the corrosive levels of pollution in the atmosphere and the discovery of asbestos in unexpected places, we have only now been able to fully understand the full investment required for this project."
The Commons Commission has also revealed the sheer scale of the work required to restore Elizabeth Tower to its former glory.
All 1,296 pieces of glass in the tower's clock dials are to be replaced with mouth blown alternatives, removing "poorly selected" pieces that have been added in earlier restoration work.
Each new piece of stone for the tower is being brought in from a quarry near Doncaster to be "completely re-carved" by stone masons, the Commission said.
Green and black paint, added to the clock dials and stonework over the years in a possible bid to hide the effects of pollution, has also been removed with "solvents and tiny brushes", in favour of the original Prussian blue of the original design.
Commons bosses said the restoration of the tower, which forms part of a wider multi-billion pound refit project across the Parliamentary estate, is still expected to be completed as planned 2021.
The latest cost estimate comes after Conservative MP Mark Francois was forced to shelve a campaign to have Big Ben ring out at the moment Britain left the European Union. Officials had estimated that it would have cost £500,000 to put the restoration work on hold in order for the bell to ring out.