Mr Lawn said they had to dump ruined stock, rip up drenched carpet and dry out the store before rebuilding could begin.
"We then repainted the walls which were water stained, replaced and repainted the front half of the ceiling and had the draw units fixed which were left sagging as they're not designed to hold water," he said.
Covered by insurance, up to $60,000 was spent fixing the store while a further $100,000 was spent replacing the lost stock, he said.
Humanity Books saleswoman Colleen Archibald said despite only deciding they would reopen late last week the news had already travelled quickly through word of mouth.
"Business has been very steady. Normally we might have someone in every half hour but today it's been every 10 minutes because the customers are starting to discover we're open again."
Mr Lawn said customers would be pleased they had reopened as the store was starting to field desperate calls from customers wanting art supplies during the end of the repairing process.
Now focused on moving on, Mr Lawn chuckled as he said at least the next 10 years' worth of maintenance has been done in three months.