"It was a good effort by the guys and we'll have a presence there all night just in case."
It was originally thought that two cleaners were missing in the building but Crawford confirmed all staff members are now accounted for.
Fire Service shift manager Andrew Norris said there were no injuries.
The buildings is close to the Harewood Fire Station, and the first truck was there within three minutes.
NZME reporter Ben Aulakh, who is at the scene on Wairakei Rd, said there were still seven or eight fire engines on site, and plenty of smoke in the air.
"I just heard one of the fire officers talking to one of his colleagues, and it looks like they're going to be here for most of the night.
"But I think that's just going to be dampening down the building and making sure that everything's safe."
Victoria Nichols, 26, lives two doors down. She said the black smoke was so thick it could be seen blocks away.
Nichols said the Fire Service appeared to be getting on top of the blaze and the flames have died down.
Police told her family they would let them know if they need to evacuate but it was unlikely.
Nichols said she wasn't surprised a fire started tonight as the evening felt "eerie".
"It's peculiar to know that it's so close but the weather is so warm it's not unquestionable.
"It's one of those warm nights where you can tell something's going to happen. It's a combination of the full moon and warm weather. It's got an eerie feeling."
Norris said firefighters initially had trouble locating the fire but it soon became obvious, with smoke coming out of the roof.
He said the blaze was at the rear of the old building.
"It is a large fire. The building is substantial in size. At this stage we're not sure how much is involved in fire."
An employee at a local sushi shop said the fire was "quite big" and the area was cordoned off so no one can access it.
Airport Guesthouse owner Deb Jackson went down to have a look at the blaze.
"There were flames and an acrid looking black smoke."