More than 6000 homes in Canterbury remain without a primary heat source.
So far, 3935 homes with family members deemed vulnerable - such as the elderly, disabled and pregnant - have had heat pumps or solid fuel burners installed under the Government's Winter Heating Programme.
The figures show 6028 homes are still to be fitted with the heating appliances.
Fletcher Construction took over the programme in Christchurch from the Energy Efficiency & Conservation Authority in February.
Chief executive Mark Binns says Fletcher has taken on about 500 contractors who are installing about 120 heating devices a day, six days a week.
He says Fletcher Construction is trying to improve that rate to get the remaining homes completed as quickly as possible but he's reluctant to put an end date on the programme.