Is attic insulation worth it in 2026?

Yes — for the vast majority of US homes built before 2010, attic insulation is the single highest-ROI energy upgrade. Typical 2026 savings: $300–$900/year on heating + cooling for a 1,500 sqft home upgrading from R-19 to R-49. Cost: $1,500–$3,500 installed. Payback: 1–4 years on operating cost alone. Federal 25C covers 30% of cost up to $1,200/year. Utility rebates add another $200–$1,500 in most states. Attic insulation also extends HVAC life by reducing run-time and improves comfort dramatically (no more upstairs-bedroom temperature swings). The fastest-payback energy upgrade in the US residential market.