The redevelopment of one of Scotland's most important art museums, and the "jewel in the crown" of Glasgow, will cost up to £66m.

Half the cost of revamping the museum that holds Glasgow's renowned Burrell Collection, an A-listed but dilapidated building in the south side of Glasgow, will be borne by the city council, new papers reveal today.

Glasgow City Council, according to papers for its Executive Committee, are expected to fund up to 50 per cent of the total cost of the radical revamp of the museum.

The remainder of the cost is hoped to be split between the Heritage Lottery Fund, which is considering a £15 million application, a major fundraising campaign and grants from other public bodies.

The £66m total - considered to be the project's first official budget - is £20m more than the organisers of the redevelopment,which will see the museum in Pollok Park close in 2016 and reopen in late 2019, had previously estimated.

It was previously said by Glasgow City Council that the revamp would cost around £45m, a number insiders described as an early estimate and "notional" last night.

The new figure for substantially upgrading the existing museum compares to the £74m cost of the Riverside Museum, a completely new building, and the £28m cost of revamping the Kelvingrove Art Gallery and Museum.

The masterplan for the project, a plan which will see more than 90 per cent of the 9,000-strong collection put on display, a four-fold increase on the current display, has now been completed.

The current one and a half floors of display space at the museum will be increased to three floors, including its basement.

The A-listed building, opened in 1983 building and designed by Barry Gasson Architects, will be also given a much-needed new roof and new windows.

There will also be improved café and shop and a new "civic events space" outside the museum.

The fabric, interior and plant of the building will also be radically overhauled - with green energy sources including solar panels and even, potentially, power from the nearby White Cart river at Pollok House.

The Executive Committee of the council is being asked next week to approve capital funding of £4.91m to further develop the proposition.

The £60m to £66m estimate includes costs associated with the refurbishment of the building, improvements to access, the redisplay of the collection and the costs of looking after and removing the temporary collections from the museum.

It also includes works to the areas surrounding the Burrell Collection and some improvements to "access and orientation" in Pollok Country Park.

The report adds: "At this early stage, it is not possible to be certain over either the out-turn costs of the project or the level of external funding that will be secured."

While the building is closed, a selection of its artefacts - collected by Sir William Burrell and given to the city in a Deed of Gift in 1944, will be shown in Kelvingrove Art Gallery and Museum and also toured around the world to major art museums and galleries.

The Council's Executive Committee will meet on April 2 to consider the proposals.

Ahead of the decision, Councillor Archie Graham, the chair of Glasgow Life and depute leader of Glasgow City Council, said: "Sir William devoted more than 75 years of his life amassing one of the world's finest, single personal collections - and he gave it all to Glasgow.

"We have a moral duty to protect and enhance what is undoubtedly the jewel in our cultural crown by providing a newly refurbished home which is worthy of its world-class status."

The council report says that the deteriorating fabric of the building is "endangering the security of the Collection."

It adds: " The building has suffered from issues with the roofing system over a period of years and significant leaks have formed.

"Although remedial repairs have been carried out in recent years, a major overhaul is required to secure the integrity of the building fabric and the protection of the Collection.

"Visitor numbers have fallen significantly partly as a result of the deteriorating condition of the building but also, as is evidenced in visitor research, by a deficiency in the visitor offer and as a result of barriers to access.

"The proposed refurbishment and redisplay will address the issues associated with both the visitor proposition and the failings of the building fabric and systems, providing a suitable, sustainable home for Sir William Burrell's Collection within Pollok Country Park. "