It appears that the fire may have been caused by hot embers being dropped behind the property. It is the second fire like this with a shed burning down in Maraekakaho this week.
Fire Safety Officer, Mike Finucane said it was an accident waiting to happen with a large number of costumes nearby.
The close proximity of neighbouring wooden-constructed homes was also a real concern.
"People shouldn't be randomly disposing of live ashes, Mr Finucane said.
They should think more carefully about where ashes are dumped as the can remain alight for some time. It's useful to house these in metal buckets away from structures," he stressed.
President of the Napier Repertory Players Incorporated, Anne Corney said Ms Marshall was in the right place at the right time.
"She did a great job, she saved our second home. Members of the theatre are practically living here at the moment, to get things right for opening night which is tonight and she did an amazing job."
Mr Pritchard said if it hadn't been for Ms Marshall spotting this fire so early, she would never have prevented the Little Theatre from being raised to the ground.
"Also, it's a big night - it's opening night, and even though the smoke damage is an issue... the show will still go on," he said.