The Fire Service wants sprinklers to be mandatory in all buildings after a fire at a Harvey Norman store in Porirua on Sunday.
Under current law, only buildings with a high life risk, including apartments, elderly care homes and hospitals, need to be fitted with sprinklers.
Fire engineering manager Simon Davis said although commercial buildings may not be occupied, lives are still in danger.
He said the biggest risk is to firefighters who put themselves in harm's way to put out the fires.
