Nelson's Elma Turner Library will close indefinitely after it was revealed heavy ceiling tiles pose an earthquake risk.
It comes after two Earthquake Prone Building notices were issued to Nelson City Council's Civic House last month, after issues with its ceiling tiles were also identified.
An inspection of the library last week found some tiles were heavier than expected - weighing between eight and 11 kilograms. Anything over 7.5kg is considered a risk if not properly restrained.
The inspection also found that the ceiling tiles were in a two-way grid, fixed at its perimeter to partitions and walls, but with no visible diagonal bracing.
Chief Executive Pat Dougherty said the library would be closed from today as a precaution while it learnt more about the risk and how it could be mitigated.
New information about the weight of the tiles was concerning, particularly when combined with the vulnerability of library users - such as older adults and children - and a lack of furniture that could offer protection in the event of a major earthquake, he said.
"Closing a much-loved community facility, even temporarily, is not an easy decision, but on the basis of what we know so far, we are not prepared to accept the level of risk the ceiling tiles at Elma Turner Library present to our community.
"Unfortunately, the library needs to be closed as a precaution while we learn more about the risk and what we can do to mitigate it."
Council had identified the ceiling tiles posed a risk and set aside $200,000 funding in this financial year for remediation work. It had not yet been completed due to staff shortages and an issue identified with the tiles being used for heating purposes, but will now take place with urgency.
Engineers will inspect the tiles and consider if they pose a significant life safety hazard.
Council will also investigate if the tiles can be secured in the interim.
This work has already been undertaken in parts of Civic House, where galvanised aluminium channels have been attached to brace the tiles, but it is unclear if this will also be appropriate for Elma Turner Library.
It was not known how long the library will remain closed for, but the council estimated it could be up to three months.
Council staff were looking at options that could include expanding online library services and increasing hours at other branches (Stoke and Nightingale libraries) as well as considering the potential of opening a pop-up library in the Central City.
Library manager Sarina Barron said as well as being difficult for customers, the closure would be hard on staff.
"Library staff thrive on the interaction they have with the public, but at least the Covid-19 lockdowns have provided us with some valuable experience in how to operate differently and provide many of our services remotely. We ask that our community bear with us as we once again change the way we operate."
Community and Recreation Committee chair Tim Skinner said he recognised the inconvenience caused to the public, but the decision to close Elma Turner Library was the right call in terms of safety.
"We cannot in good conscience allow this building to continue to be occupied knowing what we know about the weight of the tiles. We hope the community understand why we need to close as a precaution and hope we can get the library back up and running soon."
The site of the Elma Turner library has been touted as a potential location for the construction of a new library, after Nelson City Council's plan for a $46m riverside library was found to be threatened by rising sea levels.