Mr Ive, who lives in Ohauiti Rd, said he could see the smoke from Hairini Bridge, and rushed down to the scene and saw the building engulfed in flames.
"My world crumbled. I used to own four shops, now it's three. I guess it [the fire] started in the workshop but I don't really know for sure or why the fire started yet."
Mr Ive, who also owns Action Equipment stores in Katikati and Hamilton and Action All Terrain motorcycle store in Waihi Rd, said there had been a lot of gear in the Glasgow St workshop.
"I feel most upset for customers who had dropped off equipment such as chainsaw and ride-on mowers to be repaired on Thursday ... I'm praying I'm fully insured."
Mr Ive said the insurance assessment had commenced, and the replacement cost for the building could be as much as $2 million.
"At the end of the day no-one was injured, which is a blessing and it is only money. A building can be replaced but you can't replace a life," he said.
Mr Ive said despite the blow, he hoped to be operating again in a "reasonable capacity" by the end of next week, and was blown away by the many offers of assistance he had received, including from business owners.
A huge crowd formed quickly as plumes of thick black smoke billowed across the central city which could be seen as far away as Otumoetai, Hairini, Ohauiti and the Kaimai Ranges.
That included representatives from a number of other businesses in the same street. Vehicle access to Glasgow St was closed off for most of the day and Elizabeth St was closed between Takitumu Drive and Cameron Rd. Fire crews from Tauranga, Greerton and Mount Maunganui, both paid and volunteers, responded with 30-35 firefighters involved in fighting the blaze.
Assistant Area Commander Jeff Maunder said he was the first firefighter on the scene after seeing the smoke while driving in his car, and the building was already well engulfed.
Mr Maunder said the fire was contained quickly within the building within 20 to 25 minutes but fire crews remained at the site for most of the day to ensure the fire was extinguished completely.
The building had a mezzanine floor, which presented some challenges, and inside were some high pressure gas cylinders that potentially could have exploded, and needed cooling down.
The cylinders were removed by the Fire Service hazard materials unit, he said.
Tauranga Fire Brigade senior station officer Kevin Cowper said exactly where the fire started was hard to tell because of the severe damage. But eye witness accounts suggest it may have started in the rear of the building, which was where the worst damage happened. The cause of the fire was yet to be determined, but there was no reason to believe it was suspicious, he said.
Fire crews were continuing to dampen down little hot spots last night but once the fire was fully out, the site would be secured and handed back to the owners, he said.
Local builder Mark Polley said he could see the flames and smoke from Cameron Rd, and rushed to the site fearing one of his client's businesses was on fire.
"The fire was massive. It was just unbelievable," he said.
Neighbouring businesses Vehicle Testing Bay of Plenty Limited and Harry Cox Panelbeaters 2004 Limited escaped damage thanks to the quick actions of fire crews.
Harry Cavanagh, who owns Harry Cox Panelbeaters, said he could see the smoke for miles.
"I'm surprised with the amount of huge black smoke and the wind, the fire didn't spread to other buildings. The fire service did a fantastic job to contain the fire as quickly as they did. Thank goodness it wasn't a normal working day and no-one was inside the building," he said
Alex Edwards from BOP Vehicle Testings said she initially feared it was her leased premises that was engulfed after getting a phone call telling her her building was on fire.
Ms Edwards said it was hard to watch, knowing a neighbour's business had been destroyed.