Faced vs. Unfaced Insulation: What’s the Difference

Published on November 27, 2025   |   By Attic Pro Care, Inc

People know the struggle of unbearable heat in summer and warmth leakage in winter. Not having reliable insulation can take away the mental peace of anyone. How could there be peace when the HVAC system doesn’t perform well, and the electricity bill only rises in extreme weather? The indoor environment becomes similar to the external environment because there is no efficient insulation inside the home. Summer heat, high electricity bills, frustration buildup, and the list goes on.

Finally, when people decide to upgrade their insulation setup in their homes, they need some guidelines. Without having an expert, a person could make a wrong decision, and that decision could lead to back-to-back problems like the above. So, you will have to choose either a faced or unfaced insulation setup. These are the common types of fiberglass wool insulation found in many homes. Instead of making mistakes in the selection process at the hardware store, get help from this guide. It will make your decision easier, and you will probably get a better idea and durable results that will reduce your energy bills, too.

The Core Difference: It’s All About the Vapor Barrier

To understand the core difference, you need to know about fiberglass insulation first. Unless you know what it is and how it works, it will be hard to understand the difference.

What is Fiberglass Insulation?

It is a thick glass wool that works as a barrier between the wall and the indoor temperature. What it does is absorb the heat and slows down its conduction from the wall to the indoor environment. If it is summer, it slows the heat. If it is winter, it blocks the cold from passing through the walls. It is a thick barrier that prevents the change in indoor temperature and helps the HVAC system maintain its optimum performance. The HVAC system is the primary concern every user has because the external temperature affects its ability to reduce the electricity bill.

If there is no insulation, there will be excess load on the HVAC system, which will affect its performance. If there is a load on it, there will be an impact on the electricity bill, and no user wants to face high electricity bills. Neither in summer nor in winter do users want high electricity bills affecting their monthly budget. Moreover, people who don’t have HVAC systems do not want to suffer in the heat and cold in summer and winter, respectively.

What is Faced Insulation?

This is one of the two types of fiberglass insulation that has a special layer of kraft paper on it. You might have seen some homes with such insulation, but do you know the purpose of faced insulation? There must be a reason for that, and that reason is here.

Purpose of Faced Insulation (Vapor Barrier Protection)

The kraft paper works as a barrier between the moisture and the fiberglass wool. Since there is a high risk of moisture buildup in any type of insulation, kraft paper helps to prevent it. It prevents the water particles present in the air with its shiny and smooth surface. This is why it is a suitable insulation for places like basements, crawl spaces, and even attics where the risk of moisture is high. These places trap moisture more than other areas of a house. This is why people choose faced insulation to block the moisture growth on the insulation.

Besides, the Kraft paper on the insulation gives a cleaner and more finished appearance. It looks to be more presentable insulation than the unfaced type. It is also known as a vapor retarder because it prevents the vapor from getting absorbed in the fiberglass wool coming from indoor heat. Usually, it happens in attics and basements, and installing faced insulation is the best decision.

Where Faced Insulation Works Best

Again, it is suitable for places like exterior walls, new attics, high-moisture basements, and crawl spaces. Make sure the kraft paper’s side comes outside or against the wall because it prevents moisture from going inside the fiberglass wool. So, you will need to install this faced fiberglass insulation where the risk of moisture buildup is high. Places where the ventilation is poor need the faced insulation. Whether it is an attic, basement, or crawl space with poor ventilation, you should use this type of insulation.

What is Unfaced Insulation?

The second type is an unfaced insulation, which has no kraft paper on it. It is just raw glass wool that provides insulation without giving any protection from moisture. In appearance, it looks like a thick layer of pink or beige wool. That makes it suitable for insulation in both summer and winter. However, it is more suitable in winter because it blocks the airflow and slows down the spread of cold passing through the walls. The external walls absorb cold from the outdoor environment, which makes them conduct it into the indoor environment. However, fiberglass wool slows down and stops the flow of cold through its high thickness and molecular structure.

Purpose of Unfaced Insulation (Thermal + Sound Control)

The purpose of this type is to block the cold, heat, and sound. However, it can’t prevent moisture since it doesn’t have any kraft paper on it. However, the thermal resistance or R value is usually between 2.9 and 3.1. Both faced and unfaced types have the same R value because the only difference between them is the kraft paper. The moisture retarder is not present in the unfaced one, and this is why it is suitable for layering purposes.

If there is existing insulation, people choose the unfaced type for further layering. Therefore, there is no need for a moisture barrier because the layers will prevent moisture. Besides, it is more useful for places where you need soundproofing, too. Some places need insulation against noise and cold/heat, and unfaced type is suitable for it at a lower cost.

Best Places to Install Unfaced Insulation

Places that already have insulation but need further layering are the best choice for unfaced insulation. It works best when it is placed on top of existing glass wool insulation. However, it gives a raw appearance, and it is better to install it in attics. Why attics? Because attics conduct lots of heat and cold from outside to the indoor environment, and unfaced insulation has a raw appearance. In this way, you can insulate the attic without worrying about its ugly and raw appearance of fiberglass wool. These are the places where guests don’t visit.

Also, it is more cost-effective because it has no kraft paper. People who don’t have any risk of moisture or condensation in their homes or workplaces can use it.

The Summer Problem: Why Fiberglass Alone Can’t Stop Radiant Heat

Everything looks fine until there is a problem. This problem is about the summer, when users need something that can allow airflow for high ventilation. It is not just about slowing down the heat conduction, but also about the air regulation. Since fiberglass wool is a thick and warm insulation, you can expect heat trapping in summer. The sun will be heating the walls in summer for hours, and the fiberglass wool will absorb that heat. The problem comes when the heat is trapped inside.

The Science Behind It

If we discuss in detail, both faced and unfaced fiberglass insulations work like a sponge. They absorb heat and slow its spread. However, the heat remains trapped inside it. It is like a sponge absorbing water, and starting to become heavy. As a result, it becomes a heat-trapping medium, which needs something to release the heat present in it.

How Radiant Heat Travels Through Roofs and Walls

When the sun rays keep striking a roof for hours, radiant heat penetrates through the roof. That radiant heat is what causes trouble for people inside a building. The continuous spread of radiant heat from the sun to the indoor environment increases indoor temperature.

What fiberglass insulation does is absorb this heat through the roof deck. It keeps absorbing heat until it becomes saturated with it. As a result, the same heat starts leaking into the room or the entire home.

The Solution: Adding a Radiant Barrier to Your Insulation

What if there is something that can reflect radiant heat instead of absorbing it? The reflection process is way better than the absorption process. If the heat is reflected, there will be high prevention of heat transfer from the outdoor to the indoor environment.

Some people go for “Attic Pro Care” for efficient radiant heat reflection. It not only prevents the heat waves from entering the indoor environment, but it also reduces the risk of heat trapping. It is about the installation of aluminum radiant barriers that reflect the radiant heat instead of absorbing it. Thus, the risk of heat spread in the room is reduced by over 90%.

There are two ways of using radiant barriers. The first is with fiberglass wool, and the second is without it. Both will perform differently, and the cost will also be different.

Hybrid System: Fiberglass Wool + Radiant Barrier

If we look at the hybrid system, it contains fiberglass wool with an aluminum layer. The aluminum layer works as a radiant heat reflector, and the fiberglass prevents the remaining heat transfer. As a result, summer and winter become bearable. Also, the HVAC systems start working better. For instance, the heat waves will not be able to pass through the radiant barrier. Even if some waves penetrate through them, the fiberglass wool will absorb them to keep the indoor environment unchanged. A hybrid is suitable for regions where winter is dominant throughout the year. People can also install the radiant barriers on existing fiberglass insulation for a hybrid solution. You don't need to throw away your fiberglass; you just need to add a reflective layer of aluminum foil on it.

Radiant Barrier Only: Best for Hot Climates

Using only radiant barriers is also effective because the heat reflection is very efficient in both weather. Neither external heat in summer can enter, nor internal warmth in winter can escape. If someone lives in a hot region where the summer is dominant throughout the year, radiant barriers are the best choice. They are lightweight and more cost-effective for users. All they will do is reflect the radiant heat coming through the roofs and walls.

Explanation

Choosing radiant barriers will provide multiple advantages in terms of performance and overall cost. For instance, if someone uses Attic Pro Care’s radiant barrier foil, they will get the benefits below.

• Radiant barriers can reflect around 97% of the heat before it hits the fiberglass insulation.
• It will keep the existing faced/unfaced insulation cooler, so that it can work better.

Result

Users will get double the advantage of installing hybrid insulation in both weather. The glass/fiberglass wool will handle the winter’s cold by preventing the interior warmth from escaping. In contrast, the Attic Pro Care’s radiant barriers will reflect maximum heat in summer. Users will not have to go for any other option after having this permanent solution.

Installing Radiant Barriers Over Existing Insulation

Some people already have insulation, and it could be challenging for them to have it removed for a newer one. What if there is a better idea, which is also cost-effective? That is the addition of radiant barriers of Attic Pro Care. They are aluminum foils that one can have installed on the existing fiberglass insulation.

Why Moisture Control Matters (The Mold Problem)

It is not about ordinary aluminum foil that will work on the existing insulation, but something better. There is a high risk of mold because of condensation caused by moisture buildup. Installing random aluminum foils will reflect radiant heat, but won’t prevent moisture buildup. That means you need something else, like Attic Pro Care’s perforated radiant barriers.

Perforated Radiant Barriers by Attic Pro Care

What makes perforated radiant barriers of Attic Pro Care the best choice is the efficiency they provide. They can prevent the mold by continuously resisting the moisture buildup. Especially in summer, heat will not be able to cause water vapor on the barrier’s surface because of its perforation. The surface is different from ordinary solid foils.

How Perforated Radiant Barriers Work

They have tiny breathable holes on their entire surface. These tiny holes make the biggest difference. When the heat strikes the cold radiant barriers, the moisture starts building up. However, the tiny holes in radiant barriers prevent the condensation process. What they do is reflect the heat up and let the moisture escape. Then the risk of mold is eliminated in this method. That’s why people who fear mold growth in their attics, basements, and crawl spaces often choose something like that.

Benefits Of Perforated Radiant Barrier

As a result, there is no moisture buildup, and the space doesn’t get clogged with mold. There is neither mold nor any mold smell in the place of insulation.

Solid vs. Perforated Radiant Barriers: The Two Rules

• If you are installing radiant barriers on an attic floor, always use perforated foils. The reason is the moisture prevention inside the attic.
• If you are stapling them to the basement or crawl space, use solid or unperforated foils. Here, the reason is the moisture prevention on the upper portions of basements and crawl spaces.

Installation Cheat Sheet: What Type of Insulation to Use

Here are some tips or cheats to help users choose the right type of insulation. Since you know about three types: faced, unfaced, and hybrid fiberglass insulation, let’s make it easy for you to select. Selecting each type will be easier when you know about the scenarios. So, here they are.

• Scenario A: If you want to install insulation on a new wall, choose faced fiberglass wool. The faced insulation has kraft paper that prevents moisture from entering the glass wool.
• Scenario B: If it has to be installed on an existing insulation or old wall, use unfaced fiberglass wool. Since an existing insulation already has some wool on it, there is no need for a kraft paper layer.
• Scenario C: If you want to reflect radiant heat efficiently without risk of moisture, choose Attic Pro Care’s radiant barriers. They are aluminum foils that can prevent heat trapping to optimize the HVAC system’s performance.

Tip

Using a hybrid version of radiant barriers and fiberglass wool can be more beneficial than using bare fiberglass wool. If you live in a cold region, it is better to go with either fiberglass wool or a hybrid version, which also contains radiant barriers. If you live in a hot region, it is better to go with just radiant barriers or a hybrid version.

Conclusion

It is not just about insulation through heat or cold absorption, but more than that. It is about efficient radiant heat reflection that only comes when people choose Attic Pro Care. Whether someone goes for faced or unfaced fiberglass wool, their home is only half-protected if they don’t use radiant barriers.

Don’t let your fiberglass insulation absorb the sun’s heat anymore. Contact Attic Pro Care today for a free quote and affordable installation of radiant barriers. We have professionals who decide the best whether someone needs perforated radiant barriers or any alternatives.