Is R-19 enough for a wall?

R-19 suits 2x6 exterior walls in many climate zones, but check your local code for the required R-value. It is thin enough for 6.25 in. cavities.

Do I need a vapor barrier with this roll?

Yes, in most exterior wall applications. This roll is unfaced, so a separate vapor retarder is needed where code requires one.

What framing does the 15 in. width fit?

It fits 16 in. on-center studs, leaving room for the stud faces. For wider spacing or irregular bays, cut and piece it.

Is it safe for people sensitive to formaldehyde?

It is made with the ECOSE binder and is formaldehyde-free, and it carries GREENGUARD Gold certification. Still wear gloves, a mask and eye protection when installing.

How much does one roll cover?

About 48.96 sq ft per roll. For a 10 ft. by 8 ft. wall, plan on roughly two rolls.

Is $69.69 a good price?

That is the best new price across the two stores listing it as of November 4, 2026. Compare the per-square-foot cost against other R-19 rolls before buying several.

Where can I buy the Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll?

9 stores we checked sell it, including Zoro, eBay, Carr Hardware, DK Hardware, Do it Best.

Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll

Best price now

$69.69at ZoroObserved at 2:04 PM

Prices are checked against each store and labelled with when.

Visit Zoro

Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll

Best price now

$69.69at ZoroObserved at 2:04 PM

Prices are checked against each store and labelled with when.

Visit Zoro

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It checks today's price at every store, compares the alternatives and answers in about a minute.

Our take on the Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll

This is a 15 in. x 39 ft. unfaced fiberglass roll with an R-19 rating, 6.25 in. thick, covering about 49 sq ft. It is made with ECOSE binder, so it is formaldehyde-free and GREENGUARD Gold certified, and it uses recycled glass. The 15 in. width suits 16 in. on-center framing, and the unfaced form is meant for wall cavities and between floors where no vapor barrier is needed. The best new price is $69.69 at Zoro as of November 4, 2026, with two stores listing it new.

Best forFilling 16 in. on-center wall cavitiesSound control between floorsBuyers who want formaldehyde-free insulationSmall jobs needing about 49 sq ft

Pros

R-19 in a 6.25 in. thickness
Formaldehyde-free ECOSE binder
GREENGUARD Gold certified
Made with recycled glass
Unfaced roll cuts easily to fit

Cons

Unfaced: no vapor retarder included
Only about 49 sq ft per roll
Fiberglass needs gloves, mask and eye protection
15 in. width leaves gaps in wider or irregular framing

Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll prices at every store

ZoroNew
In stock
$69.69Observed at 2:04 PM
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Also available at

eBayCheck price at eBay
Carr HardwareCheck price at Carr Hardware
DK HardwareCheck price at DK Hardware
Do it BestCheck price at Do it Best
Home CentralCheck price at Home Central
Ideal True Value Home CenterCheck price at Ideal True Value Home Center
ArborCheck price at Arbor
True ValueCheck price at True Value

Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll price history

Lowest price we've seen: $30.23 on Nov 4 at Arbor. Tracked across 9 stores since Nov 4.

What reviewers say

Owner feedback on Knauf ECOSE rolls is generally positive, with people noting the softer feel and less itch than older fiberglass and little odor. Complaints center on the unfaced format and on rolls running short for larger jobs.

Pros

Less itchy and less dusty than older fiberglass
Little to no smell out of the bag
Holds shape and stays in the cavity
Cuts cleanly with a utility knife

Cons

Unfaced rolls need a separate vapor barrier
Coverage per roll is small for big rooms
Compression can lower the effective R-value

Specifications

Form: Rolls
Product Type: Fiberglass Insulation
Insulation Type: Thermal, Acoustic
Insulated Plasterboard: No
Material Type: Fiberglass
Facing: Unfaced
Material Composition: Formaldehyde-free
R-Value: R-19
Suitable Surfaces: Interior walls, Between floors
Coverage Area: 48.96 sq ft/pack
Thickness: 6.25"
Length: 39'2"
Roll Size: 15 in. x 39 ft.
Width: 15 in.
Certifications: GREENGUARD gold certified
Environmental Rating: Gold
Recycled Content: Recycled glass
Weight: 12.73
Color: Naturally brown
Solution For: Sound control

Questions and answers

Is R-19 enough for a wall?: R-19 suits 2x6 exterior walls in many climate zones, but check your local code for the required R-value. It is thin enough for 6.25 in. cavities.
Do I need a vapor barrier with this roll?: Yes, in most exterior wall applications. This roll is unfaced, so a separate vapor retarder is needed where code requires one.
What framing does the 15 in. width fit?: It fits 16 in. on-center studs, leaving room for the stud faces. For wider spacing or irregular bays, cut and piece it.
Is it safe for people sensitive to formaldehyde?: It is made with the ECOSE binder and is formaldehyde-free, and it carries GREENGUARD Gold certification. Still wear gloves, a mask and eye protection when installing.
How much does one roll cover?: About 48.96 sq ft per roll. For a 10 ft. by 8 ft. wall, plan on roughly two rolls.
Is $69.69 a good price?: That is the best new price across the two stores listing it as of November 4, 2026. Compare the per-square-foot cost against other R-19 rolls before buying several.
Where is the Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll cheapest?: At Zoro, for $69.69, as of our latest check.
Where can I buy the Knauf R-19 15 in. x 39 ft. Unfaced Fiberglass Insulation Roll?: 9 stores we checked sell it, including Zoro, eBay, Carr Hardware, DK Hardware, Do it Best.

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