DFW Home Insulation Data Report 2026: What 1.87 Million Property Records Reveal

What a Home's Age Tells You About Its Insulation

A home's year of construction is the single strongest predictor of its insulation condition. Building codes have evolved dramatically: the U.S. Department of Energy notes that homes built before energy codes were adopted often have little to no insulation. Texas adopted its first mandatory energy code in the late 1990s, meaning millions of DFW homes were built with no thermal envelope standard at all.

Based on the IECC code evolution and standard builder practices for each era, here is how the 1.87 million DFW homes break down by estimated insulation condition:

Homes by Decade Built

The DFW housing stock spans over seven decades of construction. The largest single cohort — 425,873 homes (22.8%) — was built before 1970, during an era when residential insulation was either absent or minimal. The 2000s saw the highest volume of new construction (340,346 homes), driven by the DFW population boom.

Notable trend: Average home size nearly doubled from pre-1970 (1,567 sq ft) to the 2010s (2,843 sq ft). Larger homes have more ceiling area exposed to attic heat, which means the cost of under-insulation grows with square footage. A 2,800 sq ft home with R-13 in the attic loses significantly more energy than a 1,400 sq ft home with the same R-value — but both need the same upgrade.

County-Level Analysis

The four DFW counties tell very different stories. Dallas County has the oldest housing stock (median year: 1976), while Collin and Denton counties are dominated by post-2000 construction. This geographic split has direct implications for insulation condition and energy costs.

Dallas County stands out: nearly 4 out of 5 homes were built before 2000, and 70.4% predate 1990. The median home was built in 1976 — a period when Texas had no residential energy code and builders routinely installed R-13 fiberglass batts (if any insulation was installed at all). According to the Department of Energy, homes from this era are the most likely to be significantly under-insulated.

City-by-City: Where the Oldest Homes Are

Within the DFW metro, the insulation landscape varies dramatically by city. Established inner-ring suburbs have housing stock that is overwhelmingly pre-2000, while newer exurbs on the metro's edge are almost entirely modern construction. Below are the 25 largest cities by property count.

The pattern is geographic: inner-ring cities (Dallas, Richardson, Garland, Mesquite, Irving) have 74–89% of homes built before 2000. Outer-ring cities (Frisco, Prosper, Princeton, Aubrey) are almost entirely post-2000 construction.

This means a homeowner in Richardson or Garland is statistically far more likely to have inadequate attic insulation than a homeowner in Frisco or Prosper. The insulation gap is not evenly distributed — it is concentrated in specific, identifiable parts of the metro.

What This Means for Energy Costs

The U.S. Department of Energy reports that heating and cooling account for 50–70% of total household energy consumption. In DFW's hot-humid climate (Climate Zone 3A), cooling is the dominant cost driver. The EPA estimates that homeowners can save an average of 15% on heating and cooling costs by air sealing and adding insulation to recommended levels.

Research from Oak Ridge National Laboratory shows that dark asphalt shingle roofs — the standard in DFW — run 50–70°F hotter than ambient air. On a 100°F day, that means roof-deck temperatures of 150–170°F. In a home with R-13 insulation (the condition of an estimated 621,585 DFW homes), that thermal energy transfers largely unimpeded into the living space. Our DFW Attic Temperature Report documents this effect in real DFW homes, with peak attic readings exceeding 145°F.

For context, the National Weather Service recorded 23 days at or above 100°F in DFW during the summer of 2024 — the 14th hottest on record. As summer temperatures persist or intensify, the energy penalty for under-insulation compounds. See our Texas Insulation Requirements Infographic for how building codes have evolved to address this gap.