Inside, the air conditioning ducts dangled precariously from the collapsing roof.
The floor was flooded with charred debris and murky waters streaked with coloured dye from ink cartridges and paints.
Mr Bootten said if the store had been equipped with sprinklers it would still be standing.
"It would have controlled the fire if not extinguished it."
He said sprinklers were expensive and often building owners didn't want to pay for them.
Warehouse Stationery did have a fire hose in the rear of the shop, only metres from where the fire was suspected to have started.
"They're just a garden hose that gives out a bit more water," The cause of the fire was still uncertain and a full investigation involving both insurance companies and the Fire Service would follow.
It was reported yesterday an electrical fault may have started the fire.
"We understand everything was turned off at the close of business yesterday but still have to talk to the staff member who closed the store.
"At this stage there are no suspicious circumstances."
When The Daily Post was at the site yesterday senior firefighters Gary Benfell and Chris Deboer were wearing oxygen tanks and masks as they hosed down smouldering piles of debris.
The fire forced some Central Mall businesses to close temporarily but most were open again by midday yesterday.
However, Batchelors Photo Centre, Ma Higgins and Telecom remained closed for the day.
Telecom, which shares a wall with Warehouse Stationery, had extensive smoke and water damage and a partly collapsed roof.
Store owners Damon and John Stewart said they lost all their stock but did not know the dollar value.
Damon Stewart said the shop would hopefully be re-opened by Christmas but in the meantime, a kiosk would be opened in Central Mall. It should be open from Saturday, he said.
Ma Higgins owner Charlie Windell said his shop also shared a wall with Warehouse Stationery but did not suffer any serious damage. Losing power for nine hours had caused big problems for the business, forcing him to close for the day, he said.
"We've had to replace all the cold food and have lost a day of trading."
Mr Windell said normally over the Christmas period Ma Higgins served 300 to 400 customers a day.
Batchelors Photo Centre manager Karyn O'Driscoll was allowed into the store at midday and spent the afternoon mopping up water. She hoped to be trading again today.
"It's just a nuisance for us. It's a day lost that we can't do anything about."
The Warehouse Group's Des Flynn could not be contacted by The Daily Post but was reported elsewhere as saying staff were "fairly traumatised" and the fire was a big shock. He said the business would try to employ Rotorua's 15 Warehouse Stationery staff elsewhere.
Clarke Contractors was called in to help with the clean-up yesterday and arrived with two diggers and a bobcat. Owner Wayne Clarke said it was "disheartening" to be involved in the demolition as he had worked on the store's construction 16 years ago.
No one was in the building when the fire started and no firefighters suffered smoke inhalation.