What the work saves
Type a year of energy bills. See ENERGY STAR's own upper bound for each kind of winter work, and which of your steps earn it.
Your bill
Runs in your browser; nothing you type is sent. Add up twelve months of gas and electric bills, or use a round guess.
- Seal the drafts and insulateup to $240
ENERGY STAR: sealing air leaks and adding insulation can save up to 10 percent on annual energy bills. Source
0 of 5 done: find the drafts with a sheet of paper, caulk the trim, weatherstrip what moves, put plastic film over the drafty windows, seal the holes into the attic, check how deep the attic insulation is
- Seal the ducts in cold spacesup to $240
ENERGY STAR: sealing and insulating ducts can improve heating and cooling efficiency by as much as 20 percent, and heating and cooling is nearly half of a home's energy. The bill share is our arithmetic on those two figures. Source
0 of 1 done: seal the ducts in unheated spaces
- A smart thermostatup to $100
ENERGY STAR: about $100 a year with a certified smart thermostat, for homes with high heating and cooling bills or that sit empty much of the day. Source
0 of 1 done: set the thermostat to 55 before you go
Each line is an upper bound on its own. They overlap, so they are never added into one total.
A worked example
On $2,400 a year in energy bills:
| Work | Up to, per year |
|---|---|
| Seal the drafts and insulate | $240 |
| Seal the ducts in cold spaces | $240 |
| A smart thermostat | $100 |
Why the lines are not added up
Each line is ENERGY STAR's upper bound for that work on its own. They overlap: a house that holds its heat better has less heat for its ducts to lose. Adding them would promise more than any of the sources does, so the page never shows a total.
Where the numbers come from
Sealing and insulating: up to 10 percent of annual energy bills. Ducts: up to 20 percent better heating and cooling efficiency, on the roughly half of a home's energy that heating and cooling use, which is our arithmetic and comes to about 10 percent of the bill. The thermostat: about $100 a year, and only for homes with high heating and cooling bills or that sit empty much of the day. A real house can save less; none of these is a promise.
The work itself
The steps behind each line are on the checklist, and the ones you have done are marked here. For the drafts, start with the paper test; for the ducts, see the furnace guide.
Sources
- ENERGY STAR: Seal and insulate with ENERGY STAR energystar.gov
- ENERGY STAR: Heat and cool efficiently energystar.gov
Drafted on October 26, 2026 with a language model from the pages listed above, each opened that day, and sampled by the editor after publication. Every figure is computed by the same code the tools run, and a test fails the build if one stops matching.
Found an error? See Corrections.