The Energy Efficiency Conservation Authority has for the past two years been running the Energywise campaign, offering subsidies of 33% for upgrading insulation (to a maximum of $1300) and $500 subsidies for clean heaters.
"We're finding that New Zealanders from all walks of life are noticing a real difference in the warmth of their home once they have had insulation properly installed. Half of New Zealand homes have substandard insulation," EECA chief executive Mike Underhill said.
More than 120,000 New Zealanders have upgraded their homes using the subsidy, including 7.8% of Otago's 73,872 homes.
Smart Energy Solutions South Dunedin branch manager Dean Murray said the company usually insulated 18-20 houses a week. It was important to have good insulation as well as a good heater, he said.
"If it's being run in a fully insulated home, the device [heater] is going to run a lot cheaper. The idea is to get the home to the desired temperature quickly, and hold on to that temperature so that the heat pump is switched off for long periods of time."
If a house had a heater but bad insulation, "it's like filling up a bath tub with the plug out. You're never going to hold on to that water", Mr Murray said.
Karen Broad, of rental property management company Cutlers, said while the company had seen several landlords using the programme to upgrade their rental properties, not everyone liked the scheme.
"One of the reasons a few haven't is the pricing. It's actually just about cheaper to go through a tradesman for the insulation and install it," she said.
"Some of the prices we've had come through the business services have just been astronomical and even when you take off the $1300 discount, it's still cheaper to just go out and buy it all from [a hardware store] and install it."
Between the government subsidy and homeowners upgrading their houses themselves, she estimated about 30% of the properties Cutlers managed had been upgraded over the past two years.
