Bristol City Council has more than doubled the budget for refurbishing the Bristol Beacon to £106.9 million
The venue, previously known as Colston Hall, closed its doors in the summer of 2018 with plans to redesign the interior and reopen two years later.
But series of setbacks slowed the progress of the project and it's now expected to reopen in 2023.
The updated budget for the project was outlined in a report just released by the City Council.
The increased cost is because of the discovery of previously unknown structural issues in the building, which is 150 years old.
Bristol City Council says the project is being paid for by external funding, the council’s own capital programme and Prudential Borrowing.
Marvin Rees, Mayor of Bristol, said: “Bristol Beacon has been an iconic city centre venue for 150 years.
“It’s unique cultural, economic, and social value to Bristol means that pausing or abandoning the project would be an irretrievable loss to the city, its arts and culture organisations and citizens.
“We now know what secrets the building holds, and while this has meant a higher than expected cost to modernise and re-open the venue, our commitment to Bristol Beacon is so strong that investment remains the best financial and strategic option for the city.
A report from KPMG in 2017 predicted the Bristol Beacon would contribute a potential £253.7 million to the city's economy in its first twenty years of operation after reopening. The figure was based on the business plan of Bristol Music Trust who run the venue.