Knauf R-11 Kraft-Faced Fiberglass Insulation vs Knauf R-19 Unfaced Fiberglass Insulation Roll
Buy the Knauf R-11 roll for walls, ceilings and floors where you need a vapor-retarding kraft facing and a low price per square foot. Buy the R-19 unfaced roll for deeper cavities, sound control between floors, or where a separate vapor barrier is already planned. The R-11 has traded between $18.98 and $54.99 since October 31, 2026, while the R-19 has held at $53.99.
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Knauf R-11 Kraft-Faced Fiberglass Insulation
Knauf Fiberglass Insulation
Choose the Knauf R-11 if you want a kraft-faced roll that covers about 88 sq ft per pack and costs far less per square foot.
Pros
- Kraft facing acts as a vapor retarder, so no separate barrier is needed in many wall jobs.
- Covers about 88 sq ft per pack, roughly 1.8 times the R-19 roll.
- Formaldehyde-free and GREENGUARD Gold certified.
- Made with recycled glass and LEED eligible.
What separates them
| Knauf R-11 Kraft-Faced Fiberglass Insulation | Knauf R-19 Unfaced Fiberglass Insulation Roll | |
|---|---|---|
| R-value | R-11 | R-19 |
| Facing | Kraft faced | Unfaced |
| Thickness | 3.5 in | 6.25 in |
| Coverage per pack | 88.13 sq ft | 48.96 sq ft |
| Roll dimensions | 15 in x 40 ft | 15 in x 39 ft 2 in |
| Sound control | Not rated for acoustics | Marketed for acoustic and sound control |
| Vapor barrier | Built-in kraft facing | Requires a separate barrier |
| Price per sq ft | About $0.22 at the $18.98 low |
Price history
$54.99$18.98
- Knauf R-11 Kraft-Faced Fiberglass Insulation: lowest $18.98 on Nov 2 at Menards.
- Knauf R-19 Unfaced Fiberglass Insulation Roll: lowest $53.99 on Oct 31 at True Value; $53.99 on Nov 2.
Prices at every store
Knauf R-11 Kraft-Faced Fiberglass Insulation
- AW Graham LumberCheck price at AW Graham Lumber
- WalmartCheck price at Walmart
- Carr HardwareCheck price at Carr Hardware
Knauf R-19 Unfaced Fiberglass Insulation Roll
- True ValueCheck price at True Value
- Do it BestCheck price at Do it Best
- ZoroCheck price at Zoro
Specs compared
| Spec | Knauf R-11 Kraft-Faced Fiberglass Insulation | Knauf R-19 Unfaced Fiberglass Insulation Roll |
|---|---|---|
| R-Value | R11 | R-19 |
| Form | Roll | Rolls |
| Product Type | Insulation | Fiberglass Insulation |
| Insulated Plasterboard | No | No |
| Material Type | Fiberglass | Fiberglass |
| Facing | Kraft Faced | Unfaced |
| Material Composition | Fiberglass/Steel | Formaldehyde-free |
| Coverage Area | 88.13 sq ft/pack | 48.96 sq ft/pack |
| Thickness | 3.5" | 6.25" |
| Length | 40 ft | 39'2" |
What reviewers say
Knauf R-11 Kraft-Faced Fiberglass Insulation
Buyers of R-11 kraft-faced rolls generally report it cuts and staples easily and does the job for interior walls. Complaints center on itchiness during install and on the facing tearing when handled roughly.
What people mention
- InstallationPraisedOwners say the rolls cut and staple fast, which suits weekend DIY work.
- ItchCriticisedBuyers report skin irritation and want gloves and long sleeves.
- FacingMixedThe kraft facing works as a vapor retarder but tears if pulled hard.
- Coverage
Questions and answers
- Which is better for an exterior wall in a cold climate?
- The R-19 gives more thermal resistance, but it is unfaced, so you need a separate vapor retarder on the warm side. The R-11's kraft facing handles that in one step but insulates less.
- Which one covers more area per pack?
- The R-11 covers 88.13 sq ft per pack versus 48.96 sq ft for the R-19. You need roughly 1.8 R-11 packs to match one R-19 pack's coverage.
- Is the R-19 worth the higher price?
- At $53.99 it costs about $1.10 per sq ft, against about $0.22 per sq ft for the R-11 at its $18.98 low. The R-19 is worth it when you need the extra R-value or sound control; otherwise the R-11 is far cheaper.
- Which is better for sound between floors?
- The R-19. It is marketed for acoustic control and its 6.25 in thickness adds more mass than the 3.5 in R-11.
- Do both need a vapor barrier?
- No. The R-11 has a kraft facing that acts as a vapor retarder. The R-19 is unfaced, so plan a separate barrier where your code requires one.
- Are both safe for indoor air quality?
- Yes. Both are formaldehyde-free and GREENGUARD Gold certified, and both use recycled glass.
More comparisons
- Knauf Fiberglass Insulation vs Owens Corning R-19 Fiberglass Insulation
- Owens Corning 15 in. W X 470 in. L X 6.25 in. 19 Kraft Faced Fiberglass Insulation Roll 48.96 sq ft vs Knauf Fiberglass Insulation
- Owens Corning R-19 Faced Fiberglass Insulation Roll 23 in. x 39.2 ft vs Knauf R-19 Standard Unfaced Roll Fiberglass Insulation 15 in. x 39 ft.