What is the difference between faced and unfaced insulation?

Author: Cornell Schneider  |  Last update: Saturday, June 13, 2026

The Difference Between Faced And Unfaced Insulation Faced just means that kraft paper is attached to the insulation itself. The paper helps improve the sturdiness of the insulation so it doesn't fall down as much. Unfaced insulation is just as good as faced, but it doesn't have that paper attached to it.

When should you use unfaced insulation?

Unfaced insulation is great for new construction, remodels, walls, floors, ceilings, basements, attics and crawlspaces. It's best used for interior wall applications that do not face the outside and also in rooms that don't need moisture control, like living rooms, dining rooms and studies.

Which is better, faced or unfaced insulation?

For example, if you need extra soundproofing or don't want to spend time installing a separate vapor barrier, then face may be the best option for you. However, if cost savings are more important than convenience, then unfaced may be the better choice in this case.

Does it matter which way faced insulation is installed?

(The general rule for insulation is that the facing always goes toward the conditioned space.) The second layer of insulation should be unfaced so that moisture doesn't collect between the layers.

Does faced insulation need to be stapled?

If you're using faced insulation, install it with the vapor retarder positioned down toward the room. Hold the insulation up with one hand, while stapling the flange on both sides every 6" - 8" with the other hand. Leave a little extra on each end to cover the top plate of the outside wall.

When to Use Faced or Unfaced Insulation

Can you install insulation wrong?

Besides safety concerns, installation inexperience can result in insulation mistakes that can affect both the quality of your insulation and installation. Improper placement can leave gaps and cause energy loss, lessening the insulation's lifespan.

Does faced insulation still need a vapor barrier?

Last edited by Jim Underwood; 12-19-2013 at 9:52 AM. If you use faced insulation and staple the flanges to the studs, you do not need a vapor barrier. The vapor barrier is used when you use un-faced batts (without the paper).

What is the difference between R13 and R19 insulation?

R13 insulation is generally more affordable, which makes it an attractive option for budget-conscious projects. However, R19 insulation offers better long-term advantages because of its higher R-value.

Should I use faced or unfaced insulation in my garage?

Faced insulation is also a good idea if you are putting in first time insulation. Perhaps you've liked the warmth and energy protection of an installed insulated garage door and want even more insulation. If you're already adding insulation over existing insulation, faced insulation isn't necessary or suggested.

Should you put plastic over insulation?

Yes, covering your insulation with a vapor barrier plastic before installing drywall is crucial. It prevents moisture buildup that can lead to mold, rot, and even structural damage. A polyethylene vapor barrier also adds a layer of fire protection, making your home safer.

Can you double up faced insulation?

Any new batt or roll insulation added on top of existing insulation in the attic needs to be without a vapor retarder (face). Most vapor retarders on fiberglass are made of kraft paper. The presence of this paper vapor retarder on top of between layers of insulation can trap moisture leading to mold or even rotting.

What is R13 faced insulation used for?

R13 batt insulation is typically used to attenuate sound in interior wall cavities. It is akin to a large blanket, designed specifically to fill a wall, floor, or ceiling cavity.

Why is faced insulation cheaper than unfaced?

For one, the paper backing in the insulation makes it more combustible than unfaced insulation. Additionally, layers of faced insulation cost slightly more than unfaced insulation because of the vapor barrier. On average, faced insulation costs about $0.10 to $0.25 more per square foot than unfaced insulation.

Where should you not put insulation?

Never place insulation close to water heaters, oil burners or anything hot. The backing is especially flammable and will be a major fire hazard for your home.

Is Tyvek a vapor barrier?

Is DuPont Tyvek® a vapor barrier? No, DuPont Tyvek® is not a vapor barrier. It is made with unique material science to keep air and bulk water out while allowing moisture vapor inside walls to escape.

Can I put R19 in a 2x4 wall?

The DOE Insulation Fact Sheet (DOE/CE-0180) can be ordered from the Energy Efficiency and Renewable Energy Clearinghouse or accessed from the Internet at www.ornl.gov/ roofs+walls. Fiberglass and rock wool batts—2x4 walls can hold R-13 or R-15 batts; 2x6 walls can have R-19 or R-21 products.

Is R15 worth it over R13?

R15 insulation offers slightly better thermal insulative properties than R13. Some of its formats are a fraction of an inch thicker than R13, making it more effective at helping with energy efficiency. However, the difference is minimal. R15 is slightly thicker than R13 for spray foam and blown-in cellulose.

What is a good R-value for exterior walls?

According to the U.S. Department of Energy, R-values for exterior walls in colder climates should be at least R-13 to R-23. In milder climates, a lower R-value may be sufficient. For example, in a moderate climate, an R-value of R-13 to R-15 is typically recommended.

When should I use faced insulation?

Kraft-faced insulation should be installed in exterior walls, exterior basement walls, and attic ceilings by pressing the product into the wall cavity with the paper side facing outward, towards the installer. The insulation should be snug in the cavity, but not compressed.

Can I use plastic sheeting as a vapor barrier?

For crawl space projecs that require a vapor barrier installed within walls, builders commonly use a thinner plastic sheeting option such as 6 mil, but for the best durability in the crawl space, our vapor barrier experts instead recommend choosing 8 mil plastic sheeting.

Is it OK to leave faced insulation uncovered?

Faced insulation

Kraft and standard foil facings can burn and must not be left exposed. If an exposed application is required, use FSK-25 flame-resistant faced insulation.

Is it OK to put new insulation over old insulation?

The answer is yes, you can put new insulation over old. But there are some circumstances that would require insulation removal first, such as in the case of contaminated insulation from pests, water or smoke. Moisture is the biggest culprit, as it can lead to mold and mildew, as well as ceiling and roof rafter rot.

Should electrical go behind or in front of insulation?

Wiring – When wiring exists in the cavities that are being insulated, simply split the insulation so that it is placed around the wire on both sides, allowing the wire to be comfortably nested inside the insulation.

What happens if you install faced insulation backwards?

If installed incorrectly, moisture can become trapped between the facing and cause mold, rotting, and reduced R-value.

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