Do You Have to Insulate Interior Walls?

To insulate or not insulate? We know the answer to this question!

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The question of adding insulation to interior walls is what bothers many homeowners, especially if they don’t know whether their home is already insulated. So if you have moved into a new house recently and you don’t know whether it has insulation or not, this article willbe useful for you to read!

We will tell you why indoor insulation is needed for any household and what benefits it gives to you. Also, you will learn what types of insulation are most commonly used. In addition, we will explain why your interior walls can often remain cold even if you heat your entire house!

Do You Need Insulation In Interior Walls?

Is indoor insulation for walls a must? Well, we would say yes, it is. But of course, it is up to you to decide whether you need to install it or not. Nevertheless, we would recommend you think about it thoroughly. See, insulated indoor walls have many perks and benefits that are definitely worth the time and effort spent on installing insulation!

Reinforced sheets of insulation and noise suppression on the wall

Below, you can read about several most common and obvious advantages to insulating your interior walls. Like that, you will know what you are going to invest your money and time into.

Indoor Insulation Reduces Noises

Many homeowners choose to insulate their interior walls because they want to create a sound barrier between the rooms. However, insulation can also help you make your indoor space more quiet and protect it from the noises from the street (e.g. from your noisy neighbors or their kids/dogs, etc.). 

Do You Have to Insulate Interior Walls?

Of course, you should note that no insulation can completely soundproof a room! However, interior insulation can significantly reduce noise transfer. And if you are a light sleeper, sound dampening in the walls of a bedroom will be especially important and helpful for you!  

Insulation Provides Better Energy Efficiency

Interior wall insulation functions the same as exterior wall insulation. That is, it reduces the rate of heat transferring from one room to another. If your home has no interior insulation, be ready that the outside air will enter your house easily, raising and lowering the temperature of your rooms to uncomfortable levels. 

Interior wall insulation

As a result, such temperature fluctuations will make your HVAC unit to work harder in order to bring your home to the programmed temperature. And guess what? That’s right, it will increase your utility bill!

Insulation Works As Fire Protection

This is the feature of insulation that people often forget about for some reason. However, insulation can help you make your home safer. Fire-resistant wall insulation is able to slow the spread of flames, thus keeping fire bordered to a smaller area, allowing you to escape. It also protects your home and belongings from more extensive damage.

You can use mineral wool that is fire-resistant and often used as a fire stop with a 1- to 3-hour fire rating. It doesn’t spread flames or produce smoke. As for the fiberglass and cellulose treated insulation with fire retardants, they are both noncombustible, but can still spread a certain amount of flames and produce some smoke. 

But even so, insulation products made from these materials can achieve a 2- to 3-hour fire rating. We would only not recommend you sue batts for insulating your home since they are often faced with paper, which burns easily and can spread flames.

Insulation Improves Moisture Control

Moisture develops in your home and spreads from regular activities like showering, cooking, and washing. But if this moisture condenses in your walls, it can lead to mold, rot, mildew, and water stains! 

Since mold and mildew present serious health hazards to you and your family members, insulating your interior walls can reduce this problem. For example, you can opt for special vapor-resistant membranes that can be attached to your insulation and will prevent condensation. 

Now you know what benefits indoor insulation has and why you should definitely consider installing it in your home if you still don’t have it.

Your Insulation Options for Interior Walls

If you have never had to insulate your home before, you might be wondering what type of insulation is best to use. And since there are plenty of options available these days, making a choice can be rather complicated! 

In general, you have several options for indoor insulation. And the best thing you can do is to talk to an insulation expert about which insulation type is best for you should you have decided to repair, replace, or install interior insulation. However, you can already check out the most commonly used types of indoor insulation. Like that, you will at least approximately imagine what you might be offered.

Fiberglass Insulation

Fiberglass insulation can be blown in or installed in batts. It is the most inexpensive option for insulation, but it is difficult to install a layer that is thick enough to be effective. Also, batts are often not recommended if you need a fireproof insulation since batts can easily catch up fire!

Cellulose Insulation

Cellulose insulation is a type of blown-in insulation. It is made from recycled material that is then treated with chemicals to make it resistant to mold, insects, and fire. Cellulose is the eco-friendliest insulation on the market.

Foam Insulation

Foam insulation is a recent insulation technology. Foam insulation looks and feels like shaving cream. However, when it dries, it forms a nearly impenetrable barrier against airflow.

These types of insulation have certain nuances regarding their use. For example, if you are still building your home, batt and loose-fill insulation will be easy to install. But if you want to add insulation to your existing interior walls, you will have to decide whether you want to open up the walls or not. 

Also, it’s good to know that the most common forms of insulation (e.g. fiberglass, cellulose and mineral wool) are available in loose-fill form. This means it can be blown into the wall through a hole of 1/2 to 2 inches, which means there is no need to tear the whole wall apart. Besides, this form of insulation is more efficient than batts because it fills in the tiny spaces that batts leave open.

Injection spray foam insulation is another option for insulating the cavities of your existing interior walls. And even if the wall already has some insulation, you can still inject the spray foam in to create a more airtight seal. 

What Are My Interior Walls Cold?

This is the problem that quite many homeowners face when no matter how well you heat your home, the walls remain cold! Of course, it leads to a higher energy waste tus raising your bills. But why does it happen?

Old Or Poorly-Installed Wall Insulation

The walls of your home might be cold because insulation is old or it was poorly installed. If this is the case, then the insulation between the inside of your home and the outside is no longer effective. As a result, your walls get cold when outside temperatures drop significantly.

To determine if this is the cause of the cold walls, you can either take out a few pieces of drywall from each interior wall or remove bricks from the exterior. If the insulation is damaged, uneven, or simply no longer viable, it is best to replace it.

Poorly Installed Plumbing And Fixtures

Your walls could also become cold when your plumbing pipes and other fixtures don’t have a sufficient amount of insulation around them. Sometimes, these pipes also have screws, bolts, and other fasteners that can cause voids in the walls.

If this is the case, outside temperatures and leaking water from the roof or attic will be able to penetrate the wall cavity. As a result, the wall will get colder. In addition, you will most likely have an issue with dampness and mold as well. 

The best thing to do in this case is to determine where the voids are in the wall. You can do it by following the pipes and installing insulation where it is needed. Also, if you spot a problematic fixture, it should be removed and repositioned. 

However, note that in some cases (as with heat fixtures), you may not be able to remove them yourself! In this case it's best to consult with a contractor to determine the best way to mitigate the problem.

Signs That Your Home Insulation Needs to Be Replaced

Insulation is a pretty long-lasting thing but anyway, it will have to be replaced one day. However, people are often unaware of the basic signs that tell their home insulation needs replacement. 

Do you suspect your home insulation has issues but still aren’t sure if replacement is required? Below, we gathered the most popular and well-working ways to know if your home insulation needs to be replaced:

  • The temperature in your house is uneven and changes often
  • It’s hard to get your house to the “right” temperature and keep it there
  • Certain rooms in the house have a draft
  • Your energy bill is too high
  • You are dealing with frequent leaks, condensation, or other moisture issues
  • You have a problem with rats, mice, raccoons, squirrels, insects, or other pests or rodents
  • The insulation itself appears to be wet, thin, shifting, breaking down, or falling

Should you notice at least one of these symptoms, consider checking the state of your home insulation and replace it as soon as possible!

So, now you know whether you need insulation or not. You learned what benefits indoor insulation can give you and why it’s worth time and money spent on installing it. In addition, we told you about the most commonly used types of insulation and explained what features each of them comes with. Like that, you will be able to approximately understand what type of insulation might be more suitable for you.

Frequently Asked Questions

How Much Dos It Cost To Insulate Interior Walls?

The cost to insulate interior walls will depend on the square footage of the walls and the type of insulation you use. For example, fiberglass rolls and batts will cost anywhere from $0.75 to $1.20 per square foot.

Is It Possible To Insulate My House Myself?

Yes, it’s possible. But you should still hire professionals since it guarantees proper work.

How Much Does It Cost To Insulate My Home With Spray Foam Insulation?

If you choose to go with spray foam insulation, you can expect to pay anywhere from $0.40 to $0.70 for the insulation alone. However, the labor will generally be more expensive.

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