HUDDERSFIELD'S public library and art gallery building will have to be gutted if it is to survive.
A "significant" part of its external stonework will have to be dismantled to get at the building's corroding steel frame.
And the interior will have to be taken apart for repairs to the heating and electrical systems, which need repairs.
Top councillors are being handed the details in a report when Kirklees Council's Cabinet meets next Wednesday.
A full survey has yet to be carried out - but on information so far the repair bill will be £5m.
The report says: "This would provide for repairing and strengthening the steel frame, replacing the roof, replacing electrical and heating systems and replacing the lifts.
"The costs would cover some basic reconfiguration of the building and filling in the light well to create some additional space."
Cabinet members are being asked to approve a full survey to reveal the extent of the building's problems.
The probe's cost is being kept under wraps.
Protests were launched after it was revealed the library might be pulled down because of its poor state. The report to next week's meeting says there are fundamental problems with the building.
It adds: "As all heating and electrical systems would be replaced, this will, in effect, involve taking apart the interior, particularly as the heating pipes are contained within the concrete floors.
"The concrete floors contain some asbestos, which will increase the costs for safely replacing the heating pipes."
Council leader Clr Kath Pinnock has said the library's problems cannot be ignored. The £5m does not include the cost of alternative library and art gallery services during any building work.
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