"The main part of the Cargo Shed building, which dates from the 1940s, is wooden framed with concrete foundations," Mr Averill said.
"There are issues with both the bracing and the foundations in this part of the building. The concrete extensions which were added to both ends of the Cargo Shed in the 1950s have significant structural issues and are considered unsafe due to the concrete beams spalling [large chunks of concrete breaking off]. The steel reinforcing in the walls is also badly rusted."
The Cargo Shed is owned by Tauranga City Council and leased to Creative Tauranga which sub-leases space to charity traders such as Eva's Attic and The Cambodia Charitable Trust.
Trust founder Denise Arnold said she did not want any of her volunteers "flattened".
"I thought maybe we could leave stuff in there and come back for it but they said 'no, it's really not that good'."
Mrs Arnold was told the large concrete beams at the ends of the shed were so fragile they would not stand a decent shake.
"We are quite gutted because we loved it there," she said.
Eva's Attic and the Cambodian Charitable Trust have moved to the Bethlehem Town Centre, where they would re-open this weekend .
Mrs Arnold said her biggest worry was that her regular customers would not know where they had gone or why.
Creative Tauranga chief executive Tracey Rudduck-Gudsell said she was told the ends were beyond repair and she needed to evacuate her tenants immediately.
"I basically got called over to the council and I was told they would like me to move our tenants out within a day but they gave me a week. So now we are just waiting for the report."
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