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Fri May 07 2021

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Costs double on McAlpine’s Big Ben job

2 Oct 17 Repair work to the Big Ben clock tower has more than doubled in price following detailed design work.

The Great Bell ©UK Parliament/Jessica Taylor
The Great Bell ©UK Parliament/Jessica Taylor

A closer look at the project revealed more work is needed than initially thought, the parliamentary authorities have revealed.

The cost of the Elizabeth Tower conservation project, being carried out by Sir Robert McAlpine, is now put at a headline £61m, up from £29m.

Since the initial cost estimate, the design has gone through a detailed design and technical design process. More is now known about the condition of the stonework following a further stone survey undertaken after the initial estimate. It was also found that the processes for completing the works were more complex, and therefore more expensive, than previously thought. Examples include re-glazing the clock faces, stripping and repainting metal work within the tower, and the associated sequencing which the works can be completed to ensure a high quality of workmanship: the gilding cannot be completed until all the stripping and repainting of the metal work has been completed, for example.

Ground conditions have also emerged as a factor, requiring additional work.  The quantity of utility services discovered in the ground was greater than previously thought and so more work is needed to support the weight of the scaffolding

Sir Robert McAlpine Special Projects Division was awarded the scaffolding contract and pre-construction service agreement in November 2016. (See previous report here.) The contract for delivery of the works has now been agreed and signed.

The House of Commons and House of Lords Commissions have also agreed to a proposal to increase the project’s level of risk and optimism bias.  The set-aside included in the total has therefore been raised from the original sum of £5.8m to £17.2m.

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Further to this, fire safety work, funding for which had previously been held in the budget of a different project, has been transferred to the Elizabeth Tower project for efficiency reasons, adding £4.5m to the total cost of the project. This is money that would have been spent anyway. It is not extra cost.

The estimated costs, on a like for like basis, have risen from the original feasibility study estimate of £29m to £45m. The total overall cost of the project, including VAT, risk and optimism bias and the transferred fire safety work costs, is therefore now estimated at £61m as opposed to £29m as estimated in spring 2016.

In a statement the clerk of the House of Commons, the clerk of the parliaments and the director general said “We acknowledge that there have been estimating failures and we understand the concern of the Commissions.   In advance of tendering contracts, the initial high level estimates were set at a lower level to avoid cost escalation from the market.   Subsequent estimates, using better data and more extensive surveys, better reflect the true likelihood of the costs. We believe that we now have a more accurate estimate of the cost of the works and will report regularly to the committees on the progress of work.”

Despite some silliness among MPs questioning why Big Ben’s bongs should be halted for the works, the Commissions have endorsed the decision to cease the clock chimes during the works except for national events such as Remembrance Sunday and New Year’s Eve.

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