Demand for Government subsidised home insulation is outstripping supply according to the Energy Efficiency and Conservation Authority.
Figures for July, the first month of the Warm Up, Heat Smart initiative, show great regional variation, with some areas having no approved providers.
The number of houses retrofitted throughout New Zealand in July was 3,282.
Insulation was installed in 2,519 houses, 508 houses were retrofitted with clean heating appliances and 255 houses had both kinds of work done on them.
Energy Minister Gerry Brownlee says those numbers were higher than he expected, and ahead of the Government's target of 27,500 homes in the first of four years of the scheme.
However, some regions have few or no service providers participating.
There were no homes retrofitted in Tasman or West Coast in July and just 58 in Nelson and Marlborough combined.
The Energy Efficiency and Conservation Authority is now sifting though 249 applications from potential new service providers across the country.
Mr Brownlee says while there has been early suggestion that Government grants have inflated prices, this does not appear widespread.
He says new contracts with service providers from October will be cancelled if auditing reveals unacceptable price gouging.
West Coast business struggling to cope
The owner of a heating business on the West Coast says he has more work than he can manage and he is finding materials scarce.
Bob Harris, of Air Con Buller West Coast, in Westport, says industry suppliers are struggling to cope with demand for the Warm Up Heat Smart scheme.
Mr Harris has just bought an extra truck and hired three new people as he is facing f a backlog of between 400 and 600 quotations for local jobs.
He says most customers accept that if they get in before Christmas there is a good chance that their home will be retrofitted by winter next year.