Countdown is planning to reopen today after a short but fierce fire on Monday afternoon.
The blaze started in a side storage yard, crept up the building and buckled the cladding but it was interior smoke damage that closed the doors for the afternoon and on Tuesday.
No-one was hurt and store owner Progressive Enterprises says staff have been working around the clock to clear up.
"Everything not packaged has been removed," spokeswoman Kate Porter says.
"Customers will notice a bit of a difference but the damage was mostly on the mezzanine level."
Fire brigade chief Ron Leonard says the cause is unknown.
He says it took around 15 minutes to put out the fire after the brigade received the call just before 2.30pm.
"The fire started in some stock outside in the compound up against the building's side wall."
The Waiheke Island store had a fire in 2009 which shut the building for around two weeks.
Mr Leonard says the latest incident started in the same place.
"We're not sure how. The investigation has concluded so it will remain a mystery."
The adjoining Placemakers outlet was also evacuated and closed after the fire.
Owner Lee Stickland was trying on Monday to arrange for a generator to be delivered so the store could resume normal trading as soon as possible.
- Waiheke Marketplace
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