Is 6 Inches of Attic Insulation Enough for an OKC Home?

No. Six inches of older blown fiberglass or batts is roughly R-13 to R-19, well below the R-38 to R-49 recommended for an Oklahoma City attic. Most homes with 6 inches need to roughly double or triple their insulation depth.

How 6 Inches Compares

Oklahoma City is in climate zone 3. ENERGY STAR recommends R-49 total for an uninsulated attic in this zone, and about R-38 added when 3 to 4 inches are already there. To reach R-49, you need about 16 to 20 inches of blown fiberglass or about 13 to 14 inches of cellulose, depending on the product.

Why So Many OKC Attics Have About 6 Inches

Homes built from the 1950s through the 1970s were often insulated with a few inches of rock wool or fiberglass, sometimes topped up once in the 1980s. Newer homes were often insulated to the minimum of their day, and loose fill settles over time. Cable, internet and HVAC work also disturbs insulation, leaving bare spots.

Can You Just Add More on Top?

Usually, yes. If the existing insulation is dry, clean and free of rodent droppings, new blown-in insulation goes right on top, and the two layers add together. If it is wet, moldy or contaminated, it should come out first. See should you remove old attic insulation.

Do Not Skip the Prep

Before adding depth, seal the major air leaks, install baffles at the eaves so soffit vents stay open, and weatherstrip the attic hatch. These steps cost little and make the new insulation perform as rated.

Does 6 Inches Qualify for the OG&E Rebate?

Under OG&E's posted rules, existing insulation must be under 8 inches or R-23 and the finished attic must reach at least 13 inches or R-38, among other requirements. A typical attic with 6 inches often meets the starting rule. Check OG&E's current program page for amounts and deadlines.

Attic Insulation Elite offers free attic inspections and written quotes seven days a week, 8am to 8pm. Call (405) 400-2050 or request a free quote online.