More than 13,000 cavity walls and 30,000 lofts have been insulated to date.
Council leader Mehboob Khan said: "I hope that all the residents of Kirklees will take advantage of what Warm Zone has to offer before its too late.
"The number already taking part is a fantastic achievement and demonstrates how many people in Kirklees are benefiting from the scheme."
Alongside switching their energy supplier online via price comparison sites, insulation is one of the best ways for households to cut the cost of their heating bills.
Earlier this year the government announced plans to retrofit a third of British homes with energy saving technology by the year 2020.
Click here to run an energy price comparison, and see if you could be paying less for your gas and electricity.