Faced vs. Unfaced Insulation: Which Is Best for Your Home?

Homes require insulation to help regulate the flow of heat through the walls and ceiling. By slowing the transmission of heat through the walls, the home can remain warm in the winter and cool in the summer, despite the temperature outdoors. This layer is also useful for noise reduction so that you don’t hear everything going on outside. Some insulation can also help prevent moisture from entering the home, which is a benefit for homes in humid regions and areas that get a lot of rain. However, there are significant differences with faced vs. unfaced insulation, so it’s important to know what type of insulation you are installing or replacing to ensure you select the best insulation for the home.

Faced insulation includes a paper vapor retarder.

Both faced and unfaced insulation are suitable choices for home insulation, but the differences between them help to determine the best locations within the home to install each type. The main difference between faced and unfaced insulation is that faced insulation typically has a paper vapor barrier or retarder attached to one side of the insulation. The purpose of the paper vapor barrier is to block moisture from permeating the walls and ceilings of the home. This is especially useful in humid locations, like coastal cities.

It should also be noted that some faced insulation uses vinyl or even light aluminum foil as a vapor barrier, in place of paper. These alternate materials, however, may not be approved for use in some areas, so be sure to check local regulations and building codes before choosing insulation for the home.

Unfaced insulation is non-combustible.

One of the benefits of using unfaced insulation whenever possible is that it is typically considered to be a non-combustible material. It can actually help reduce the chance of fire by providing a barrier between the interior wall and the exterior wall that slows the spread of flames or stops them entirely.

Faced insulation cannot make the same noncombustible claim due to the flammable paper vapor barrier that is firmly attached to the insulation. However, it’s common for a layer of faced insulation to be used in the exterior walls and attic ceilings to prevent water from entering the home, while unfaced insulation can be added to improve the heat retention ability and reduce the risk of fire. Just make sure that the paper vapor barrier is on the outside of the insulation stack instead of in the middle; if it’s between two insulation layers it can cause moisture to build up within the insulation, leading to mold and mildew.

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Faced insulation is easier to install.

DIYers looking for a way to make home insulation easier should consider using faced insulation over unfaced insulation because typically faced insulation is significantly easier to install. This is because the insulation is held together by the paper vapor barrier, allowing the faced insulation to be rolled, moved, and stapled without falling apart.

Unfaced insulation does not have the same cohesive strength, so it’s more susceptible to tearing during installation. Additionally, staples don’t work well with unfaced insulation, so the installer needs to rely on the insulation to cling to the wall or ceiling. Some installers will add a plastic vapor barrier over unfaced insulation to both block out moisture and help secure the insulation to the target surface.

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Consider the type and orientation of insulation before stacking.

The vapor barrier on faced insulation can cause problems if it is not taken into account when stacking insulation. If the vapor barrier is trapped between two layers of insulation it can lead to moisture build-up within the insulation and the growth of mold and mildew inside the walls of the home. The vapor barrier must always be on the outside of the insulation stack.

Cold Climates: The vapor barrier must face the interior of the home.

• If you have a layer of faced insulation installed facing the interior of the home, you must remove this layer of faced insulation before you can replace it with a layer of unfaced insulation. The layer of faced insulation can then be stacked on top of this layer of unfaced insulation with the vapor barrier facing the interior of the home.
• If you have a layer of unfaced insulation installed you can stack another layer of unfaced insulation without issue.
• If you have unfaced insulation installed and you want to install faced insulation to create a vapor barrier, you can immediately stack the faced insulation on top of the layer of unfaced insulation as long as you make sure the vapor barrier is facing the interior of the home.

Warm Climates: The vapor barrier must face the exterior of the home.

• If you have a layer of faced insulation installed facing the exterior of the home you can stack a layer of unfaced insulation without any problems.
• If you have a layer of unfaced insulation installed you can also stack another layer of unfaced insulation without issue.
• If you have unfaced insulation installed and you want to install faced insulation to create a vapor barrier, you will need to remove the existing insulation and replace it with faced insulation that has the vapor barrier facing the exterior of the home. You can then add a layer of unfaced insulation on top of this first layer of faced insulation.

Faced insulation is slightly more expensive.

There is a minor cost difference between faced and unfaced insulation. On average, faced insulation costs about $0.50 to $2 per square foot of wall or ceiling. Unfaced insulation costs about $0.50 to $1.75 per square foot. The modest difference between them indicates that faced insulation costs about $0.10 to $0.25 more per square foot than unfaced insulation, which is likely attributed to the vapor barrier. This slight increase in cost shouldn’t impact minor upgrades, though if you need to insulate the whole home or even multiple properties, the price difference may affect your decision.