Gasfitters say the Christchurch gas explosion is a reminder of the need to check for gas leaks before lighting any gas appliance.

Plumbers, Drainlayers and Gasfitters Association president Glen Burr says there are many possible ways in which gas could have leaked in the house that blew up in the Christchurch suburb of Northwood, where most streets have piped liquefied petroleum gas (LPG).

"You could have a nail in the pipe, or someone actually cut it - anything can cause it," he said.

"It could be a leaky valve. It could be all sorts of things. It's too early to determine that."


But he said the explosion was a warning to be careful with all gas appliances.

"LPG and natural gas are relatively safe, providing people get the appliance serviced by a certified gasfitter," he said.

"We don't really have many explosions in this country because it's quite regulated. But accidents do happen.

"It's a very regulated trade - this just points out the reason why we are regulated in this country to protect people, and gas is not something to be played with.

"People should check their gas installations before they actually light gas, especially gas heaters. But they don't."

Burr said only certified gasfitters were allowed to install gas appliances legally, but recent explosions in Auckland had been caused by work that was done illegally.

"There was a garage levelled to the ground and the guy who started it was very lucky he didn't get killed. That was a result of illegal gasfitting," he said.

The Christchurch house was left looking like
The Christchurch house was left looking like "matchsticks" after the explosion. Photo / Kurt Bayer

"We are very, very lucky that no one was killed this time. To have seven people come out of that, looking at the damage that was done, they are very, very lucky."


A house in the West Auckland suburb of Massey was destroyed by what was believed to be a gas leak or gas bottle exploding in April.

A house in New Windsor was blown up by a suspected gas leak in 2017.