EPA estimates that homeowners save an average of 15% on heating and cooling costs, or 11% on total energy costs, by air sealing and adding insulation. That's the most reliable savings figure published for this work.
So the benefit is a share of your bill, not a fixed amount. Here's what ENERGY STAR says, how rebates can help, and what's changed, checked on October 9, 2026.
How Much Can Air Sealing Save?
ENERGY STAR cites an EPA estimate: an average of 15% on heating and cooling costs, or an average of 11% on total energy costs, from air sealing and adding insulation in attics, floors over crawl spaces and basements. Your savings depend on your home and energy use.
ENERGY STAR explains why leaks matter: air that escapes through walls, windows, doors and other openings wastes energy and raises costs. It adds that if you added up all the leaks, holes and gaps in a typical home's envelope, it would equal leaving a window open every day of the year.
How Common Are Air Leaks?
ENERGY STAR says most U.S. homes don't have enough insulation and have significant air leaks, and that 9 out of 10 homes in the U.S. are under-insulated. So most homes have room to improve, which is why air sealing and insulation are usually done together.
ENERGY STAR also lists comfort benefits beyond the bill: less outside noise, less pollen, dust and insects, better humidity control and a lower chance of ice dams in snowy climates.
How Much Does Air Sealing Cost?
We don't publish a typical price, because we found no official source for air sealing costs. The cost depends on the size of the home and the number of leaks, so get a written quote that lists what will be sealed.
To compare quotes fairly, ask each contractor which areas they'll seal (attic, crawl space, around windows and doors) and whether insulation is included. Then subtract any rebate you qualify for and compare it with your yearly heating and cooling spend.
Are There Rebates for Air Sealing and Insulation?
Some utilities offer insulation rebates. LADWP's Attic Insulation Rebate Program pays $0.50 per square foot for attic insulation above R-19, or $0.30 at R-19 or below, plus an extra $0.25 per square foot. LADWP says attic insulation can save up to $374 a year.
LADWP's program covers attic insulation, not air sealing on its own. The insulation rebates savings guide covers LADWP's rules, and the free rebate calculator checks the programs at your address.
Has the Federal Tax Credit for Air Sealing Ended?
Yes, for 2026 projects. The federal 25C credit, which covered insulation and air sealing materials up to the $1,200 annual limit, ended for property placed in service after December 31, 2025, according to IRS Fact Sheet FS-2025-05.
Air sealing completed in 2025 can still go on the 2025 return. The guide to the federal home energy credits that ended covers the details.
Official Sources
The savings estimates come from ENERGY STAR's page (citing EPA), and the rebate figures from LADWP's own page, all checked on October 9, 2026.
- ENERGY STAR: Why Seal and Insulate?, EPA's 15% / 11% estimate and the comfort benefits
- LADWP Attic Insulation Rebate Program, insulation rebate rates
- IRS: Energy Efficient Home Improvement Credit, the 2025 limits of a credit that ended after December 31, 2025
Frequently Asked Questions
Is air sealing worth it?
ENERGY STAR cites an EPA estimate that air sealing plus insulation saves an average of 15% on heating and cooling costs, or 11% on total energy costs. Whether it pays off for you depends on your quote, any rebate and how much you spend heating and cooling now.
Does air sealing qualify for a tax credit in 2026?
No. The federal 25C credit, which covered air sealing materials, ended for property placed in service after December 31, 2025 (IRS FS-2025-05). Air sealing completed during 2025 can still be claimed on the 2025 return, within the $1,200 annual limit.
Should I air seal before adding insulation?
ENERGY STAR's estimate covers both together: air sealing plus adding insulation in attics, floors over crawl spaces and basements. ENERGY STAR describes a well-sealed envelope coupled with the right amount of insulation as what makes a real difference on utility bills.
Sealing and insulating in 2026? See the verified rebates for your address with the free rebate calculator.