The ambitious redevelopment will see the popular chain establish its national Heritage Centre at the Lichfield Street venue as well as convert the upper floors into a hotel – generating around 50 new jobs.
The original plans were officially approved by City of Wolverhampton Council last year, but Wetherspoon has submitted revisions that include an additional sixth floor set back from the front elevation of the building, to take the total number of hotel rooms to 90.
The Heritage Centre will also now occupy a larger area than originally planned, making use of the basement as well as the ground floor.
Throughout the works the city centre pub will remain open for business to the public.
The new-look pub and hotel are expected to open fully later in 2020, with a date yet to be confirmed for the official opening of the Heritage Centre.
Wetherspoon spokesman Eddie Gershon said: “The Moon Under Water is an extremely popular pub in the city.
“The planned re-development highlights our commitment to offering our customers the best pub possible.
“The addition of a hotel and heritage centre will be great additions too.
“We are proud to be investing in such a wonderful city as Wolverhampton.”
The 40,000 sq ft space above the pub, with its Art Deco frontage, has been empty for more than 30 years after being home to the old Co-op store.
The building sits opposite the Grand Theatre, who have had plans approved to expand into the former post office next door to develop a pop up theatre, while City of Wolverhampton Council is proposing to pedestrianise part of Lichfield Street.
City of Wolverhampton Council Cabinet Member for City Economy, Councillor Harman Banger, added: “This exciting project will help transform one of our key city centre streets.
“It will breathe new life into this building and forms part of the £1.1 billion investment in the city centre, further demonstrating the growing confidence in our city.
“It will deliver a significant number of jobs and for a national chain like Wetherspoon to choose City of Wolverhampton for its national Heritage Centre is an honour.”