Last month councillors approved a hike in the schemes budget, taking it to 430 the second time the expected outlay has soared in just 15 months. In mid-2023, the budget was re-estimated at around 354 million, up from the initial budget of 305 million.Purcell won consent for its revamp of the Grade I listed 19th-century town hall in January 2020. The Gothic Revival building, designed by Alfred Waterhouse, had fallen into disrepair.The project restores the buildings grand entrance hall and council chamber while adding new facilities including a caf, bar and rooftop terrace.AdvertisementManchester City Council deputy chief executive Paul Marshall said that since extra funding was requested in July 2023, constant, further challenges had been uncovered by the project team.There has not been a single week without a discovery event that has had cost and time implications, he wrote in a report to councillors last month.Marshall said the construction programme was so complex that it comprised 22,000 activities and there had not been a single month since Notice to Proceed in which the project had been in steady state.The council added that as a result of the projects many technical challenges, a number of contractors had either been stood down or asked to stay on site longer, leading to more than 80 financial claims.The project was initially expected to complete this summer. Main contractor Lendlease still has it scheduled to finish in July 2026 but this timetable is considered highly vulnerable, according to the latest report.AdvertisementMarshall told councillors that ongoing design requirements remained a major threat to hitting the latest completion target.Of the 97 per cent of packages that have achieved ready-for-construction status [as of May 2024], there are 233 early warnings relating to further information required to allow works to be progressed on site, he wrote.The risk of further delay to completion of these design activities is, together with further discovery, the principal risk to further delay to the date for completion.The latest update said the scheme was three-quarters of the way through its construction phase.As progress continues to be made, and scaffolding is removed from completed sections, more of the iconic building is being restored to public view and the exceptional quality of skill and craft delivered by these tradespeople will be increasingly evident, wrote Marshall.Lendlease and Purcell have been contacted for comment. Source:Royle Media/Lyndon SBGManchester Town Hll renovation worksProject dataArchitectPurcellStructural and civil engineerRamboll UKLandscape designPlanit-IEBuilding services and engineeringOve Arup & PartnersQuantity surveyorFaithful+GouldConstruction manager LendleaseClient Manchester City Council