The numbers for zone 3
| Your attic today | ENERGY STAR recommendation |
|---|---|
| No insulation | Insulate to R-49 |
| About 3–4 inches | Add R-38 |
| Floor over a crawlspace | R-19 |
How deep that is depends on the material. The coverage chart on the bag lists the depth for each R-value, and a good installer will show you depth markers in the attic when the job is done.
How to check your attic
- From the attic hatch, look across the floor. If you can see the tops of the ceiling joists, you almost certainly need more.
- Push a ruler straight down into the insulation in a few spots and note the depth.
- Look for flattened, wet or stained insulation, and for droppings, tunnels or nests.
- Check that soffit vents aren’t buried. Baffles keep the air path open.
Seal first, then insulate
ENERGY STAR recommends sealing air leaks before adding insulation. Gaps around light fixtures, plumbing and wiring holes, the attic hatch and duct boots let hot attic air into the house no matter how deep the insulation is. If rodents have been in the attic, the old insulation may need to come out first.
What about tax credits?
The federal Energy Efficient Home Improvement Credit (25C) covered insulation installed through December 31, 2025. It doesn’t apply to work done in 2026. Some North Texas utilities and electric providers run their own efficiency programs, so it’s worth checking before you book.
How we do it
We remove old or contaminated insulation when needed, seal gaps and rodent entry points, add baffles, and blow in new insulation to the level your attic needs. See our attic insulation service.
Questions
What R-value do I need in my attic in Dallas?
DFW is in climate zone 3. ENERGY STAR recommends R-49 for an uninsulated attic, or adding R-38 if you already have 3–4 inches.
Is there a tax credit for attic insulation in 2026?
The federal 25C credit covered insulation installed through December 31, 2025. It doesn’t apply to 2026 work. Check your utility or electric provider for local programs.
Should I remove old insulation before adding more?
Only if it’s wet, moldy, or contaminated by rodents. Otherwise, seal air leaks and add new insulation on top.
Sources: ENERGY STAR: Recommended home insulation R-values · U.S. DOE: Insulation and air-sealing essentials (2021 IECC table) · IRS: Energy Efficient Home Improvement Credit (25C)