More than half of the country’s whole-home energy-efficiency retrofit programs offer free energy audits and financing to pay for the cost of an energy efficiency retrofit, according to a new study.

The report, from the National Home Performance Council (NHPC), provides information on the 126 programs across the U.S. that promote whole-house approaches to residential energy efficiency. These organizations provide outreach and, often, financial support to homeowners who want to carry out energy-saving renovations. Typical retrofit measures include insulation, air sealing, and replacement of inefficient heating and cooling systems with high-efficiency models.

The study also found that 86% of retrofit programs offer financial incentives, typically in the form of rebates, with the amount varying by program. For instance, New Smyrna Beach, Fla., runs a program that offers a $200 rebate for duct sealing and $375 for insulation upgrades, while the New Hampshire utilities offer an incentive of 75% of the cost of eligible measures up to a cap of $4,000.

State- and utility-based energy efficiency retrofit programs have expanded rapidly over the past two years in response to new funding provided by federal stimulus money and initiatives like the DOE’s Better Buildings, which encourages experimentation and innovation in home construction. For the NHPC study, researchers reviewed all energy efficiency programs listed in the Database of State Incentives for Renewables and Efficiency (DSIRE).

An energy-efficiency retrofit can not only improve comfort by tightening leaky homes, but it can also save homeowners as much as 20% to 40% on monthly utility bills, according to the NHPC, with an estimated national savings of $21 billion each year if all outdated, inefficient homes were remodeled to energy-efficient standards.