The same day the successful tender is expected to be announced for the demolishing the Tauranga City Council administration building, councillors are holding a closed workshop meeting to discuss the fate of the next building facing an uncertain future in the civic heart project – the library.

While not as leaky or mould-ridden as the now abandoned administration building, the library is at a similar age and stage and has many of the faults that decided councillors to demolish and replace the administration building.

The original building is now 20 years old and the second floor addition 11 years old. The library has a current book value of $2.27m. Adding another floor will require significant structural additions, states the David Lambie report being considered today by the City Transformation Committee.

Geotechnical assessments show the library building will likely be impacted by liquefaction in a 1/100 year earthquake event due to shallow foundations, and the position of the building at the bottom of the slope.

Like the administration building the library would protect life in the 1/100 year earthquake, but would be unable to be used afterwards.

Four options are presented to councillors.

Option one: No change. Continue to use the building as it is. It means current dampness and smell issues will not be resolved and the deteriorating glazing systems will continue to fail.

Option 2: Remediate to basic level. Replace Ground and Level 1 glazing and cladding, identify and repair damp issues, minor interior face lift, minor refurbishment of core services.

Cost: $4.8m. Seismic strengthening, exterior enhancements, interior workplace enhancements, improved toilet facilities are excluded from the estimate.

Replacing the glazing should eliminate any water issues but does introduce more natural light to the interior – and doesn't create a fit for purpose library or office standard higher than C-Grade. Following capital expenditure of $4.8m, the building value would only increase approximately $1m.

Option 3 is for more extensive remediation, more comprehensive refurbishment. Replace the exterior glazing and cladding systems, exterior architectural enhancements to create appeal, refurbish building services, in-ceiling seismic restraint works, partial interior refurbishment, layout modifications, new toilets.

Option 3 doesn't consider full replacement of building services or seismic strengthening works to 100 per cent NBS.

'We note that adding a third level to Building B is structurally not possible without significant structural upgrades which would be uneconomic in comparison to the cost of a new building,” states the report.

Option 3's estimated cost is $13.2 million. While it will result in significant building improvements it does not fully address the floor plate size, column layout and seismic rating of the structure. It also does not create a fit for purpose library facility, but does create an office environment at approximately B / B+ Grade.

Option 4 is demolishing and rebuilding. Based on the comparison with the Te Atatu Library the existing 3,715m2 structure would be replaced with an approx. 4,500m2 area building at a cost of $28.3 million. The cost is an indicative estimate only.

'The cost per meter to deliver a new fit for purpose building will naturally vary subject to scope, design and specification,” states the report.

'There will be multiple ways to deliver the desired outcome dependent on the requirements agreed through the various Detailed Business Cases.”