The sleepout had not had a smoke alarm, so it was lucky his son had woken before he was overcome by smoke, he said.
"It's a wake-up call, a big one. You never think it's going to happen to you," he said. The fire destroyed all Luke's possessions, including clothing, a television set, Sky decoder and PlayStation.
The fire spread to an adjoining garage where it destroyed tools, saddles, fishing rods and camping gear, just as the family was about to head to Kai Iwi Lakes for a camping holiday.
"Lucky the important thing survived, and that's my son," Mr Jones said.
Two volunteer crews from the Kaikohe Fire Brigade arrived within minutes, backed up by a crew from Okaihau and a rural fire tanker.
Fire Service volunteer support officer Brad Mosby said with no smoke detector in the sleepout, the teenager was lucky to be alive. Had the fire started at 3am when he was in a deeper sleep, he might not have woken.
Smoke could put people into a deeper sleep, or asphyxiate them, Mr Mosby said.
"It's not the fire that kills but the smoke."
Given the size of the sleepout, the fire would have taken seconds to develop and only minutes to "flash over," when everything in the room ignites at once. A smoke alarm would have sounded within seconds of the fire starting.
"We can't urge enough the importance of having smoke detectors in sleepouts and every room where people sleep.
"Don't put it off, do it now. This is a wake-up call," Mr Mosby said. And they needed to be correctly positioned.
Many people put smoke detectors in their hallways but if the door was closed when a bedroom caught fire it would have to be burning fiercely before enough smoke got under the door to set off the alarm.
Fire investigator Gary Beer traced the cause of the blaze to an electrical "event" in a light switch above the bed.
For advice on fire safety call 0800 693-473 and ask for a free home fire safety check. Pensioners and low-income families may be eligible for a free smoke alarm and discounts on further alarms. Cheap batteries are fine for smoke alarms, but they should be checked annually.