A church in Christchurch that was the victim of a suspicious fire didn't have smoke alarms.

The fire at St Margaret's Presbyterian in Bishopdale broke out at around 5.45am yesterday.

Fire Service spokesman Andrew Norris said the extent of the damage could have been prevented.

"There were no alarms in the building, no monitored alarms or anything like that that may have alerted us to the fire earlier which may have prevented such signifcant damage to the property."

Six fire engines were battling to put it out, before fire investigations deemed it was suspicious.

A Fire Service spokesman said it appears the building's possibly a total loss, and demolition could be likely because it's currently unsafe.

The fire damaged the church's chapel and a store room.

Minister Andrew Nicol said there are other facilities on their premises.

"So we'll certainly be getting back up and going as much as possible in the coming week. Obviously there's a fair road ahead."

Community groups who use the space are being assisted to find alternative room to house their meetings in the meantime.

"We've already been in contact with people who will be affected by what happened and working with them to also find suitable places in the community to run their meetings in the meantime," said Mr Nicol.

Police are now investigating the fire.