Christchurch explosion: Gasfitter pleads guilty after last year's destructive blast

A gasfitter has pleaded guilty to a WorkSafe charge over a destructive house explosion in Christchurch last July.

Six people were badly injured and several properties were damaged with one of them being destroyed.

The explosion happened on Marble St in the suburb of Northwood and police said at the time it was a miracle no-one was killed.

WorkSafe laid charges over the incident in July this year.

At the Christchurch District Court on Tuesday, Gas Unlimited and owner Greg Smith admitted a charge each under the Gas Act.

Smith is willing to take part in restorative justice with the victims.

Immediately after the explosion, locals Newshub spoke to said the explosion was unlike anything they had ever heard.

"Initially I thought a plane had come down," said Northwood resident Faye McGill.

"It rained glass and shingle through the house," McGill said last July.

Sentencing will happen in December.