Fire safety officer Stu Ide, of Queenstown, wants rural property owners across the district to be more mindful about ensuring they allow easy access to large emergency vehicles.
His comments were sparked by a fire callout in Wanaka on Saturday night, where two fire engines struggled to squeeze along a tree-lined Aubrey Rd driveway to access a house fire.
"People need to be aware they should have trees trimmed back to ensure compliance. You need a gap big enough for a fire engine: about 4m high and wide."
Response times to emergency callouts are a critical component for fire brigades and any delays could have serious repercussions for property owners, he said.
The Wanaka Fire Brigade was called to a house fire on Saturday about 11.30pm, when an electrical fault started a blaze in the building's ceiling, Mr Ide said.
The sole female occupant at home during the incident said "she smelt something like a barbecue" from outside the house.
"When she went inside to investigate, she noticed the ceiling was glowing," Mr Ide said.
Investigations into the cause of the fire, which were conducted yesterday, had found a nail was piercing a two-way light-switch cable.
This caused an "arcing" between the two components, which had started the fire, Mr Ide said.
The fire caused "some extensive damage" to the ceiling and interior of the roof, but was "not very visible" from outside the building, he said.
Wanaka brigade station officer Mark Strang said about 20 firefighters attended the incident.
