Robert Linterman, the authority's residential manager, said the focus was to initially install insulation.
"Only once the home is insulated can the home owner elect to install an approved heating appliance. To date the programme has delivered over 155,000 insulation retrofits and over 33,000 heating retrofits," he said.
Cold weather spurred more people into the scheme.
"It's available year-round, however there is typically an increase in uptake over the colder winter months. As homeowners feel the cold and start receiving their higher energy bills, they realise it's really something they can take advantage of," Linterman said.
The retrofit target in June was the highest for the year at 12.5 per cent compared to 9.5 per cent in July, 9 per cent in August then dropping to 8.5 per cent in September. The lowest for the year was one of the hottest months, January, at 5 per cent , he said.
The scheme was now into its fourth year, starting on July 1, 2009 and homeowners could get 33 per cent off the cost of insulation, up to $1300. That was available for all homeowners with places built before 2000, regardless of income, he said.
"EECA is working with several local councils, including Auckland Council and Wellington Regional Council, and New Zealand's major banks to provide cost effective finance, through either additional charge to the rates bill or increase to their mortgage, to cover the costs of repayment over a period of time. The cost of this to the homeowner is from $7 a week - a small price for the homeowner to pay for the comfort and health benefits they can get from an insulated house," Linterman said.