Is R-11 enough for an exterior 2x4 wall?

R-11 is the standard fill for a 3.5 in. 2x4 cavity. In cold climates, many builders add rigid foam or use a higher-R product instead.

What size are the batts really?

The listing name says 23 in. x 93 in. but the specs say 15 in. x 93 in. Measure your stud spacing and confirm the batt width with the store before buying.

Which side does the kraft facing go on?

The facing goes toward the heated side of the wall, warm-in-winter. Facing the cold side can trap moisture in the cavity.

How much wall does one pack cover?

The listed coverage is 155 sq. ft. Divide your wall area by that, then add about 10 percent for cuts and waste.

Is it safe for indoor air?

It is formaldehyde-free and GREENGUARD Gold certified. Wear gloves, long sleeves and a dust mask during install, and seal the facing.

Insulation prices move with seasonal demand, often dipping in late fall and winter. Track the price history and buy when it sits below its recent range.

Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in.

Best price now

$449.00at MyHackerTechObserved at 3:54 PM

Prices are checked against each store and labelled with when.

Visit MyHackerTech

Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in.

Best price now

$449.00at MyHackerTechObserved at 3:54 PM

Prices are checked against each store and labelled with when.

Visit MyHackerTech

Ask our agent about this product

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Our take on the Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in.

Knauf R-11 is a kraft-faced fiberglass batt for 2x4 wood-framed walls, giving about 3.5 inches of thickness and R-11 thermal resistance. The kraft facing works as a vapor retarder and the batts are formaldehyde-free and GREENGUARD Gold certified, which matters for indoor air quality. The listed coverage is 155 sq. ft. per pack, though the spec sheet's 15 in. batt width and the 23 in. name don't line up, so confirm the actual batt size before ordering. The best new price is $449.00 at MyHackerTech as of November 4, 2026, from the only store listing it.

Best forInsulating 2x4 exterior walls in wood-frame homesDIY retrofits where friction-fit batts beat blown-inBuyers who want a formaldehyde-free, low-odor battGarage, basement and interior wall projects

Pros

R-11 in a standard 3.5 in. cavity, no furring needed
Kraft facing doubles as a vapor retarder
Formaldehyde-free and GREENGUARD Gold certified
Uses recycled glass content in the binder
Cuts with a utility knife and friction-fits between studs

Cons

Fiberglass still needs gloves, sleeves and a mask
Kraft facing must go on the warm-in-winter side; wrong-side installs trap moisture
Batts must fill the cavity fully or R-value drops
Only one store lists it, so price competition is thin
Bulk pack is heavy at about 22 lbs and awkward alone

Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in. prices at every store

MyHackerTechNew
In stock
$449.00Observed at 3:54 PM
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Also available at

Stones Ace ofCheck price at Stones Ace of
Insulation4USCheck price at Insulation4US
Roofing4USCheck price at Roofing4US
Woodson LumberCheck price at Woodson Lumber

Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in. price history

Lowest price we've seen: $124.95 on Nov 4. Tracked across 7 stores since Nov 4.

What reviewers say

Fiberglass batt insulation like this draws consistent feedback: easy to cut and fit, effective when installed tight, and itchy to handle. Kraft-faced versions are liked for the built-in vapor retarder but criticised when the facing tears or the fit is sloppy.

Pros

Cuts cleanly and friction-fits between studs
Noticeable difference in wall comfort once sealed
Facing staples up quickly as a vapor retarder

Cons

Itchy fibers; gloves and a mask are a must
Facing tears easily if handled roughly
Gaps at edges hurt performance if not stuffed tight

Specifications

R-Value: R-11
Form: Batts
Product Type: Fiberglass Batts
Insulation Type: Thermal
Insulated Plasterboard: No
Material Type: Fiberglass
Facing: Kraft Paper
Coverage Area: 155 sq. ft.
Thickness: 3.5"
Batt Size: 15 in. x 93 in.
Length: 93 in.
Width: 15 in.
Installation Method: Batt Installation
Certifications: GREENGUARD gold certified
Environmental Rating: Gold
Recycled Content: Recycled glass (in binder)
Weight: 22.01 lbs
Color: Naturally brown

Questions and answers

Is R-11 enough for an exterior 2x4 wall?: R-11 is the standard fill for a 3.5 in. 2x4 cavity. In cold climates, many builders add rigid foam or use a higher-R product instead.
What size are the batts really?: The listing name says 23 in. x 93 in. but the specs say 15 in. x 93 in. Measure your stud spacing and confirm the batt width with the store before buying.
Which side does the kraft facing go on?: The facing goes toward the heated side of the wall, warm-in-winter. Facing the cold side can trap moisture in the cavity.
How much wall does one pack cover?: The listed coverage is 155 sq. ft. Divide your wall area by that, then add about 10 percent for cuts and waste.
Is it safe for indoor air?: It is formaldehyde-free and GREENGUARD Gold certified. Wear gloves, long sleeves and a dust mask during install, and seal the facing.
When is it cheapest?: Insulation prices move with seasonal demand, often dipping in late fall and winter. Track the price history and buy when it sits below its recent range.
Where is the Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in. cheapest?: At MyHackerTech, for $449.00, as of our latest check.
Where can I buy the Knauf R-11 Kraft Faced Fiberglass Insulation Batt 23 in. x 93 in.?: 5 stores we checked sell it, including MyHackerTech, Stones Ace of, Insulation4US, Roofing4US, Woodson Lumber.

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