Which is better for attic insulation?

The Knauf R-30. Its 10 in. depth gives R-30, which meets or exceeds common attic targets, while the R-13 is built for 3.5 in. wall cavities.

Which one should I use for 2x4 walls?

The Owens Corning R-13. At 3.5 in. thick it fits a 2x4 cavity; the Knauf R-30 is 10 in. and will not.

Which covers more area per pack?

The Owens Corning R-13 covers 148.54 sq ft per pack versus 69.33 sq ft for the Knauf R-30. Check price per square foot at the store to compare cost.

Is the Knauf R-30 worth the extra thickness?

Yes for attics and ceilings, where the higher R-value cuts heat flow. For walls it is the wrong product regardless of price.

Does either one control moisture?

Both have a kraft vapor retarder. The Owens Corning lists moisture control and the Knauf lists moisture mitigation with a permeance of 1.0 or less.

Which is better for soundproofing?

The Owens Corning R-13 lists acoustic insulation and noise absorption, and its thinner batt suits interior wall assemblies.

Owens Corning EcoTouch R-13 Insulation Batt vs Knauf R-30 Kraft Faced Fiberglass Insulation

Buy the Owens Corning EcoTouch R-13 for 2x4 wall cavities, where its 3.5 in. thickness and built-in vapor retarder fit standard framing. Buy the Knauf R-30 for attics and ceilings, where its 10 in. depth delivers more than twice the R-value per batt. The R-13 covers 148.54 sq ft per pack versus 69.33 sq ft for the R-30, so compare price per square foot at the store before you commit.

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