What insulation rebates pay in Denver
The amounts come from Xcel Energy's 2026 rebate summary, last read on September 29, 2026. Xcel's own page would not load for our reader on October 5, so check it for the current caps. The Colorado Energy Office page was re-read on October 5, 2026.
Xcel attic insulation
Gas-heated homes get 1.5 times the standard amounts, which works out to $750 by our math. Applies to homes heated by Xcel gas or electricity.
Xcel wall insulation
Same 30% rule. Gas-heated homes get 1.5 times, or $525 by our math.
Xcel air sealing
Gas-heated homes get 1.5 times, or $600 by our math.
State income-based rebates (HEAR)
Up to $1,600 for insulation, air sealing and ventilation while it was open. The single-family program is now closed.
Federal tax credit (25C)
The credit for insulation and air sealing ended for spending after December 31, 2025.
Working it out
Say a Denver contractor quotes $2,400 to add attic insulation. Thirty percent is $720, but the cap is $500, so Xcel pays $500. At $1,500, 30% is $450, under the cap, so you get $450. For a gas-heated home the cap goes up by half, so the same $2,400 job earns $720 under our math. The cap, not the percentage, decides the rebate on most jobs, which is why a bigger quote does not earn a bigger rebate.
What Denver homes look like
The American Community Survey (2020 to 2024) counts 359,581 homes in Denver. About 55% were built before 1980, which is roughly 200,000 homes by our math, and 17% before 1940. Only 31% went up in 2000 or later. About 51% of households rent, and 5% of homes sit in buildings of two to four units.
Insulation levels vary a lot from house to house, even on one block, so a good assessor looks at what you actually have before quoting a measure.
Start with the attic and the air leaks
Xcel's caps on the attic and on air sealing are the easiest to reach. Air sealing closes the gaps where heated air escapes into the attic, such as around recessed lights, plumbing chases and the attic hatch. The rebate for air sealing is up to $400, and Xcel's rule for insulation is also 30% of cost. Ask your contractor to price the air sealing and the insulation as one job, since insulation over leaky ceilings does less.
Heating fuel in Denver
The same survey says about 61% of Denver households heat with utility gas and 36% with electricity. If Xcel supplies your gas, the 1.5 times multiplier applies, and so the gas-heated majority of the city gets the better caps. Electric-heat homes get the standard caps. Because heat pumps run on electricity, a Denver home that is going electric should insulate first or at the same time, so the new heat pump can be smaller.
Renters and small buildings
With about half of Denver renting, most insulation decisions are a landlord's. Xcel's rebate goes to the customer who pays for the work, so ask your landlord whether they have used it. If you own a two-to-four unit building, ask Xcel and your contractor how the rebate is counted when the building has more than one meter.
What changed in 2026
Two things shrank the money for insulation. The federal credit ended after 2025. And the Colorado Energy Office closed the single-family version of its income-based rebate program in August 2026, which could pay up to $1,600 for insulation, air sealing and ventilation. If your household income is under about 80% of the county median, ask Xcel and your local weatherization office what is open for you now.
Top-rated installers in Denver
Ranked by Google reviews (minimum five). We don't take referral fees or paid placements. Ask each one if they are an Xcel participating contractor.
How to claim Denver insulation rebates
- Find out what Xcel supplies you: gas, electricity or both. That sets your caps.
- Ask for an energy assessment or at least a blower door test so you know where the air leaks.
- Get quotes that list attic, wall and air sealing work as separate lines.
- Choose an Xcel participating contractor and confirm the rebate in writing.
- Keep the invoice and apply through Xcel after the work is done.
Common questions
How much does Xcel pay for insulation in Denver?
30% of cost, up to $500 for attic insulation, $350 for wall insulation and $400 for air sealing, with 1.5 times those amounts for gas-heated homes, from Xcel's 2026 rebate summary.
Is the income-based state rebate still open?
No. The Colorado Energy Office says the single-family program is closed.
Is there a federal tax credit for insulation?
Not for 2026. It ended for spending after December 31, 2025.
Does the rebate depend on how much I spend?
Only up to the cap. At 30% the cap is reached at about $1,667 for an attic, $1,167 for walls and $1,333 for air sealing.
Should I insulate before buying a heat pump?
Usually yes, or at the same time. A tighter home needs less heating capacity, so the heat pump can be smaller and cheaper.
What to do next
Read our Denver heat pump rebate page if you are planning to go electric, or see the Denver rebate hub.
By Sam Menard. Sources, last read October 5, 2026: Xcel Energy Colorado residential rebates, Xcel Energy 2026 rebate summary, Colorado Home Energy Rebate Program, IRS residential clean energy credit. All Denver rebates → Every Xcel Energy Colorado rebate →