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How the Upgrade Ladder estimates your savings

The Upgrade Ladder turns your energy bills and a few answers about your home into a list of upgrades in the order to do them. This page explains each step and the published sources behind it. Everything here is an estimate built from data, not a measurement of your home.

1. Your bills set the scale

Every estimate scales from what you actually spend. You enter each month's electricity and natural gas bill: at least three months, and twelve is best. You can enter a 12-month total instead, though monthly bills are more accurate. If some months are missing, we fill them using your state's typical seasonal pattern from U.S. Energy Information Administration (EIA) data, scaled to your own bills rather than to a state average. We treat each bill as covering the middle of one month to the middle of the next.

Propane and heating oil can be entered in dollars or gallons; gallons are priced at your state's EIA price.

2. Where your money goes today

Your spending is split across seven end uses: heating, cooling, water heating, refrigerators, cooking, clothes drying and everything else. The split starts from the shares measured for your state in EIA's Residential Energy Consumption Survey (RECS 2020, state-level table CE3.6.ST).

If you enter 9 or more months of bills that cover winter (and summer, if you have central air), we measure your own heating and cooling share instead. Your monthly use is fitted against NOAA heating and cooling degree days for your state, or your region in California, Oregon and Washington, and the result is adjusted to a normal-weather year (the 1991–2020 average). When the bills don't support a reliable fit, for example under budget billing, we keep the typical shares. The paid report says which was used, and why.

3. What each upgrade saves

The ladder covers 28 upgrades, from a thermostat setback to a heat pump. Each has its own documented basis, mostly U.S. Department of Energy and ENERGY STAR guidance and state technical reference manuals: the engineering handbooks utility efficiency programs use to count savings. Every figure in the paid report names its source.

Window savings vary most with climate, so they come from the current manual nearest yours. In the Pacific Northwest they also depend on how your home is heated, using the Regional Technical Forum's and the Bonneville Power Administration's per-square-foot figures for gas, propane, oil, heat-pump and electric-resistance homes, priced at your state's electricity and fuel rates.

Five smaller upgrades (faucet aerators, a thermostatic shower valve, a clean furnace or air conditioner filter, boiler pipe insulation and low-E storm windows) use the Illinois manual's savings in kWh and therms, priced at your state's rates. Storm-window savings are also scaled to your state's heating and cooling degree days. In a heat pump home, the thermostat setback counts cooling only, because a winter setback can bring on the heat pump's backup heat.

Some upgrades change which fuel you use, such as a heat pump replacing a gas furnace. Those are worked out with your state's electricity and fuel prices, and an upgrade that would raise your bill at today's prices is left off your ladder.

4. What it costs

Each upgrade's cost range comes from its documented basis; for windows, water heaters and appliances, that is the Illinois or Vermont technical reference manual. Costs are adjusted to your area with RSMeans city cost indices, with materials and labor adjusted separately, and do-it-yourself projects carry no labor cost. In six Mountain states (Colorado, Idaho, Montana, New Mexico, Utah and Wyoming), heat pump costs include an allowance for altitude, because a larger unit is needed for the same heat. If you're replacing something anyway, we count only the extra cost of the efficient model. All costs are shown before rebates.

5. Putting it in order: the ladder

Upgrades are grouped into three levels: quick wins that cost little or nothing, do-it-yourself projects, and bigger investments that usually need a contractor. Within each level they are ordered by payback: the middle of the cost range divided by what the upgrade saves in a year on its own.

Upgrades overlap. Once a thermostat setback has cut your heating bill, attic insulation can only save a share of what's left. So each rung's savings are counted after the rungs before it, and the rungs add up to the total, which is lower than the upgrades added up one at a time. Your ladder shows each rung that way (in sequence) by default; a switch shows each upgrade on its own instead, for anyone who may skip some rungs. The paid report follows the same choice, and its chart shows both, with how much was lost to overlap.

6. What we leave out

Some actions are likely to help but don't have data good enough for a dollar figure. They appear in the paid report as "worth doing" and are excluded from every total. Upgrades that would save nothing for your home, or raise your bill, don't appear on your ladder.

7. Sources

8. Keeping it current

• Energy prices are refreshed from EIA at least once a year; weather data from NOAA every month.
• The reference manuals and rebate rules are reviewed at least once a year. Last review: October 13, 2026.
• The federal 25C and 25D tax credits ended for improvements installed after December 31, 2025. The report's rebate notes reflect the U.S. Department of Energy's June 2026 rules for the HOMES and HEEHR rebate programs.

9. What the estimates can't do

Questions about the method: Gregory.Brown@brolte.com.

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