Upgrading to a newer furnace undoubtedly increases energy efficiency, thanks to its superior design. Nevertheless, quantifying the exact amount of savings is challenging as multiple variables come into play. Factors such as insulation quality and the use of energy-efficient windows can affect the efficiency of the furnace. Unlike some businesses that may promise unrealistic savings figures, we prefer to take a more practical approach and suggest that you should expect to see a reduction of about 15% in energy costs following the installation of a new furnace.