The house was badly damaged and Mr Nielsen said it would be "touch and go" whether it was rebuildable.
"The front half was severely damaged by fire ... the rest of the house is damaged by heat and smoke damage."
Mr Nielsen said the house had not been equipped with smoke alarms.
Fire-safety officers have yet to determine the cause of the fire, but it is not believed to be suspicious.
The owners were out at the time.
Neighbour Heather Bannister and her daughter were the first to notice the fire and alert fire services after seeing flames coming from the roof.
"[I] ran out to check the number of the house and called up the fire department and by that time there were a lot more flames; by the time they got there it was blowing out the window.
"Everything sort of moved so fast, like fires do, I think if we'd noticed it any later the dogs wouldn't have survived," Mrs Bannister said.
"I'm just amazed they were still alive after all the smoke and the flames, it's pretty much a miracle that they were still alive."
She spoke to the house owners and offered them a place to stay.
"I just imagine that they've lost everything they have, so that's quite sad, and it's their own home. Friends all come together at times like this, you feel for them."
Mrs Bannister was relieved no one was hurt.
"They were out shopping ... They might have been killed if they had been there but if they'd been there they also might have been able to see what was happening and stop it," she said.
Wairarapa SPCA dog compound manager Ross Nixon said the labradors were quite drowsy when SPCA personnel arrived.
"If the fire brigade had not been there to resuscitate them they would have died, so it was really quite traumatic for the dogs," Mr Nixon said.
The SPCA would hold the animals for the family.
"Until they have a chance to sort themselves out, they're going through quite a trauma at the moment," Mr Nixon said.
The dogs were treated by a vet for smoke inhalation and were looking fit and healthy yesterday.
