Should You Insulate Interior Walls?

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Insulation is a vital finish for homes, especially for homes that need to regulate their temperatures. Interior walls are light, thin, and are found throughout a house. The question now is if you need to insulate your interior walls.

It is not necessary to insulate interior walls but doing so offers many benefits. Aside from just temperature control, insulation also helps make your interior walls more resistant to sound and fire.

interior of a Modern Living Room with Colored Walls

Read on as we’ll be going into the benefits of insulating your walls, the different types of insulation-finishes and their benefits, how to make the most out of your insulation, and many more!

Benefits of insulating your interior walls

Insulation is a great way to improve the overall livability, efficiency, and usage of your home. The insulation benefits are pretty numerous and highly depend on what specific type of insulation you’re looking to install on your interior walls.

Here’s a list of the benefits that you can get from insulating your interior walls:

1. Energy Efficiency

Insulation helps temperature regulating appliances (heater/air-conditioner) perform better by ensuring that the room’s temperature changes stay constant.

It would be a waste of energy and electricity usage if the heat/cold were to just escape from your room.

2. Cold-resistance

This is why insulation is a must-have if you live in an area that experiences winter. Insulation protects and allows your utilities to function despite low temperatures.

The specific type of insulation for cold-resistance are usually for lofts and foundations (basements, crawlspaces, or slab)

3. Fire-resistance

Fire-resistance plays a significant role in the construction industry. Nearly every part of your house has to meet a fire-rating requirement.

Insulation helps meet this requirement by providing fire protection, rated based on how long the material can hold off the fire before breaking down.

4. Endless choices

The insulation is to prevent things from passing through. Insulative requirements have their electrons bunched up together to prevent something like waves from entering/exiting freely.

There’s a lot of liberty given to homeowners on how they can go about insulating their houses. They have a vast amount of options at their disposals since insulation can come in all shapes and sizes.

5. Sound- resistance

As we mentioned, insulation considerably dampens the waves that pass through them. Aside from just temperature, insulation can also dampen sounds. This is great if your home has thin walls or if you have a rowdy crowd in there.

The great thing about insulation is that it can provide all these benefits for your house and are easy to install. Take note, however, that not all insulation is the same.

Some might be better at dampening sound, while others will be suited towards fire-resistance. The good news is that you can easily mix and match to get what you want!

Do you need to insulate all of your interior walls?

The answer to this question will highly depend on what you’ll use your insulation for. It’s not practical to tear down the wall behind your cabinets if you just want less sound, but it will be necessary if you need to protect the pipes inside that wall from freezing.

It’s recommended to find out whether your home already has insulation installed into it. Usually, contractors automatically install insulation for newer homes (built past 20-30 years).

However, these will deteriorate over time, and it’s best to know when was the last time your insulation material has been checked.

Parts of the house that need interior wall insulation the most

You should insulate your attic and your ground floor before anything else. These two are non-negotiable, especially if you need insulation to regulate the temperature inside your home.

1. Attic Insulation

Insulating your attic is essential because this is where heat usually escapes from the house. This heat can cause damage by letting moisture build-up or cause harm by allowing any ice on your roofing to melt prematurely, which can freeze again.

The consensus is to use fill-type insulation along with blanket-type to prevent this from happening.

insulation of a new building with foam wall

2. Ground Floor

Most of our activities are located on the ground floor of our homes. Most of the heat generated will also most probably be coming from this area, and we want to keep that in there as much as possible.

You can also efficiently insulate interior partition walls on your ground floor with some cellulose boards and foam spray.

If you live in a tropical country or experience hot weather, then don’t worry! Insulation works both ways and will also keep the cold air in (great for air-conditioned spaces)

Types of Insulation Materials

In this section of the article, we’ll want you to familiarize yourself with the different insulation materials. This is so that you can make the best choice when choosing the insulation for your interior walls.

Mineral Wool	For Blanket-type insulations, mineral wool can be any material woven into a “cloth.” Most of the time, they’re made out of stones such as basalt or slag. Great for covering vast areas and irregularly shaped rooms.
Foam	Lightweight and can be installed as either foam boards or by foam spray. Manufacturers can make it out of either polyurethane or polystyrene. Depending on the type of foam you use, it can either be used for fireproofing, waterproof or sound-proofing purposes.
Fiberglass	Cheap and offers excellent fire protection for its price. Also easy to install and is excellent at minimizing heat transfer. Fiberglass can be quite dangerous if mishandled.
Cellulose	Cheap, environmentally friendly, and has one of the highest fire-resistance ratings of all the other materials on this list. It can potentially cause allergic reactions to users and is quite challenging to work with.

Now that we’ve gone through the different kinds of materials that insulation is made out of, we can now go into the different insulation types.

5 Parts of an Interior Wall

In this section, we just want to go into a brief overview of interior walls so that you’re better aware of how insulation is installed inside them. For our purposes, we’ll be going to the parts of a non-load bearing stud interior wall.

1. Stud

Vertical members used to form as the support for the wall.

2. Plate

The plates are the horizontal members where the studs are placed on. Found on the top and bottom of the wall as well as at the bottom of windows.

3. Header

Usually found above windows or doorways. Headers are used to fill the gap between the top of the window/doorway and the upper plate.

4. Trimmer

These are other studs, usually beside windows and doorways, used to have them fit their measurements.

For example, if your studs are 1 meter apart but your window needs space for 800mm. The trimmer studs will make up the difference to let your window fit into the wall while maintaining its measurements.

5. Cripple

Cripple studs are studs found at the bottom of windows. These are used to support the window plates.

Considering how light and how hollow stud walls are, it is best to fill them up with insulative materials to provide better protection and to improve your home in general.

The great thing about stud walls is that they’re not that hard to renovate/change compared to other wall-types.

Interior vs. Exterior Wall: What’s the Difference?

Although they’re both walls, interior and exterior walls are built very differently. Exterior walls experience more structural load and are more exposed to outside elements (such as rain, snow, sunlight, wind, external noise, etc.).

Insulating your exterior walls is even more essential if you’re looking to protect your house from extreme temperatures.

Here is a brief overview of the main differences between your exterior and interior walls

Exterior Walls	Interior Walls
Thicker to allow more insulation and to act as a barrier between the outdoor elements and the indoors.	Thinner to make it easier to construct and lightweight.
They are made out of more durable materials, making them more expensive to construct.	Cheaper to construct since interior walls are usually hollow/ don’t need as much care.
Usually has the essential utilities located along with them (gate valves, meters, electric boxes, etc.)	Utilities are usually outlets, light switches, and some plumbing.
Insulating them is much more cost-effective but also more costly upfront. Provides around 35% savings in energy from temperature control if all your exterior walls are insulated.	Insulation for these walls is usually for walls close to uninsulated areas(ex. garage). Cheaper to insulate up front but does not provide as much energy saving.

Insulating both your exterior walls and interior walls is highly recommended! Aside from providing protection and making the spaces inside your house more comfortable, insulation also increases your home’s real estate value.

Conclusion

Insulating your home is a great way to protect it from the elements such as heat, moisture, and cold. You should insulate interior walls to make the home protected, more efficient and improve life quality inside the spaces.

There are many types of insulation materials, each serving its purpose. It’s recommended that you focus on insulating all your walls.