Three fire crews responded to a blaze near Southbridge, about an hour south of Christchurch, around 6.40pm on Thursday.

A man who set fire to his house while burning a wasp nest with a spray can and a lighter is lucky he didn't burn the building down, a firefighter says.

The man tried to get rid of the nest using the makeshift blowtorch through a hole in the wall to "smoke the wasps out" on Thursday night. Instead he started a fire in the wall cavity.

Three fire crews responded to the blaze at the rental property near Southbridge, 50 kilometres south of Christchurch, about 6.40pm.

Southbridge senior firefighter Ben Wilson said his crew were in "disbelief".

"It's a bit of a shock that someone might have done that.

"It's a good time to remember that aerosol cans and lighters are not a safe approach to any form of blowtorch."

Wilson told the man to "leave it to the professionals" next time he had a bug infestation.

"There was potential to lose the house, there was nothing stopping it completely engulfing the house in flames."

An exterior wall of the house on Glasseys Rd was smouldering by the time fire crews arrived.

The fire spread to wood panels within the wall and exterior cladding.

Fire crews were at the scene for about an hour.