The back wall of a Mount Maunganui storage shed burst open sending some of the 10,000 tonnes of concrete rock inside spilling out and damaging a building next door.
The building, owned by Rorisons RMD and leased by HR Cement, backs onto an industrial area on Harvard Way.
The 11m high wall gave way about 6pm on Saturday night and fell partly onto a building owned by Tauranga developer Bob Clarkson. Most of the wall and metal spilled on to an empty lot behind.
HR Cement managing director Chris Hall said he received a panicked phone call from a staff member who was stacking a load of product when the wall fell down.
"I think it's just the weight of the metal's pushed it out basically," he said. "It was bloody lucky it was an empty section just here."
Mr Hall said work was stopped immediately until engineers had could check the building to make sure it was still structurally safe.
The building was largely in-tact as there was no structural support in the back wall but the building would have to be emptied and have new slabs poured in order to fix it, he said.
The company had almost finished building another bulk storage facility so would be able to move the contents of the warehouse there while it was repaired meaning the company would not be forced to stop operating during the two to three months the work was likely to take, he said.
Mr Clarkson said the collapse had done some major damage to his property which backed on to the HR Cement warehouse.
"It's going to be a major just to fix," he said. "It's smashed the concrete tilt panels, crushed the internal guttering at the top and done some reasonably major damage.
"It's quite disastrous. If someone had been standing there they would have been killed."
Mr Clarkson said it appeared the warehouse had been over-filled.
Rorisons RMD, which owned the building, was not able to provide the Bay of Plenty Times with comment in time for this edition.
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