What does unfaced insulation mean?

Author: Buford Skiles  |  Last update: Sunday, May 17, 2026

What is the difference between unfaced and Kraft-faced insulation and how is it installed? Unfaced means the insulation lacks a vapor retarder (paper or plastic facing). Kraft-faced insulation includes a paper vapor retarder, which helps prevent mold and mildew.

Is it better to use 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 unfaced insulation need to be covered?

Unfaced insulation is a plain batt or roll of fiberglass insulation with no facing. It is Class A fire-rated, which means it can be left exposed, or used in specific fire-rated assemblies.

Does it matter which way insulation faces?

When installing faced insulation, the facing should always point toward the interior, heated, or air-conditioned space. For example: On exterior walls, the facing should touch the drywall. In attics, the facing should point down toward the ceiling below.

Which side does the vapor barrier go on?

In climates that are hot and humid, a vapor barrier should be installed on the warm side (for walls, this would be just beneath the exterior cladding, over the insulation). For very cold climates, the warm side is the interior, so the insulation should have a vapor barrier separating it from the interior wall.

When to Use Faced or Unfaced Insulation

Does order of insulation matter?

One of the most important rules of insulation installation order is to install the thickest layer of insulation first, and then add thinner layers on top of it. This is because the thicker the insulation, the higher the R-value, and the more effective it is at preventing heat transfer.

How do you get unfaced insulation to stay in place?

The unfaced insulation can be secured to the framing with staples. After securing the insulation, wrap the entire passage with house wrap and seal the seams with house wrap tape. The house wrap helps hold the insulation in place and slows airflow.

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 the vapor barrier be in or out of insulation?

Our view is that for mixed climates (aka heating dominated climate zones) the best place for a smart vapor barrier is inboard of the insulation because it will prevent conditioned air from entering the insulation layer and really help minimize or eliminate condensation.

Where not to insulate?

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.

Do you staple unfaced insulation?

using unfaced batts or rolls, allow friction to hold the insulation in place (called “friction fit method”). If a polyethylene vapor retarder is used, staple it across the unfaced batts.

Do you need a air gap behind insulation?

It provides an additional layer of insulation by trapping air and helps to prevent moisture buildup by allowing for ventilation. So, it's always recommended to leave an air gap when installing insulation, whether it's in your walls, roof, or floors.

Why is unfaced insulation more expensive?

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.

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.

What does the R mean in insulation?

R-Value is a measure of insulation's ability to resist heat traveling through it. The higher the R-Value the better the thermal performance of the insulation.

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 R13 OK for walls?

For walls, r13 insulation is a good choice in most instances, and because your basement is below the ground, there's some natural protection from the earth around it.

What is the best insulation for exterior walls?

Foam Board or Rigid Foam

Foam boards -- rigid panels of insulation -- can be used to insulate almost any part of your home, from the roof down to the foundation. They are very effective in exterior wall sheathing, interior sheathing for basement walls, and special applications such as attic hatches.

Is it OK to 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.

Can you leave unfaced insulation exposed?

If undisturbed, exposed insulation poses very little health or safety risk. For example, your attic or unfinished basement may have exposed insulation because you're not spending time there. If you find exposed insulation in other areas, however, it could pose risks.

Should I remove old insulation or just add more?

Removing old insulation is generally recommended if it's damaged, contaminated with mold, or infested with pests. However, if the insulation is in decent shape and just needs a boost, adding a new layer on top can be a cost-effective option.

What should you not do when installing insulation?

Leaving Too Many Gaps

One of the biggest problems DIY homeowners face is leaving too many gaps in their insulation. Gaps or insulation that isn't secured correctly can leave the building structure open to air and moisture leaks. Spray foam insulation is best for reaching into small cracks and any areas left open.

How many inches of insulation is good?

R-Value is a measure of insulation's ability to resist heat flow. The higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.

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