Most Households that have to qualify for ECO4 need to have an Energy Functionality Certification (EPC) score of D or below. The ranking usually means your own home has been measured up with regard to its efficiency to save lots of energy and how your house takes advantage of energy, https://eco4grants.finance.blog/2025/09/15/the-ultimate-guide-to-uk-home-insulation-and-energy-grants-eligibility/