What Is The Best Insulation For Internal Walls

What Is The Best Insulation For Internal Walls?

Find my local specialist...

Key Takeaways:

  1. Fibreglass Batts as a Top Choice: Fibreglass insulation, specifically in batt form, is highlighted as a preferred choice for internal wall insulation. The material is praised for its lightness, easy installation, and effectiveness in retaining heat.
  2. Overview of Common Insulation Types: The content provides a concise overview of four common types of insulation for internal walls: Fibreglass Batts, Blown-in Cellulose, Spray Foam Insulation, and Rigid Foam Board Insulation.
  3. Considerations for Different Insulation Types: The content emphasizes that the choice of the best insulation for internal walls depends on factors such as wall type, climate, and budget. It underlines the importance of considering the specific characteristics of each insulation type.

Home insulation is crucial for temperature regulation, energy consumption reduction, and general comfort. Several insulating solutions you’ll find on the market. 

Some common types of insulation include fibreglass, spray foam, cellulose, and mineral wool. The confounding thing is that each of them has its own set of advantages and disadvantages. Now, you may be wondering:

What is the best insulation for internal walls? 

The best insulation for internal walls depends on many things, like the type of walls, the climate, and the budget. But fibreglass insulation is thought to be the best internal wall insulation because it is light, easy to install, and does a great job of keeping the heat in. 

>> Also Read; Detecting areas of moisture/damp build up and areas of heat loss

What are the Different Types of Insulation for Internal Walls

You’ll find different types of insulation for internal walls with several advantages and drawbacks. Here, we’ll discuss the most common types of insulation for internal walls: fibreglass batts, blown-in cellulose, spray foam insulation, and rigid foam insulation.

1. Fiberglass Batts

This type of insulation is one of the most widely used forms of internal insulation. Fibreglass Batts are made of glass fibres woven into a mat and then treated with a fire retardant. They are easy to install and have a high R-value, so they are highly effective in trapping heat. 

Fibreglass batt insulation is relatively inexpensive compared to other insulation materials. However, this insulation does not provide an airtight seal, which can allow air to circulate through the walls, so take this into account before installing internal wall insulation.

fiberglass batts

2. Blown-in Cellulose

Blown-in cellulose is also a common form of insulation that is typically made of recycled paper. This substance reacts as a fire retardant before being blasted into the walls using specialised equipment.

This insulation has a high R-value and works well as an air seal. It is also easier to install than other types of insulation, making it an excellent alternative for do-it-yourself applications. Blown-in cellulose, on the other hand, might settle with time, lowering its overall efficacy.

3. Spray Foam Insulation

On interior walls and in other parts of the house, this adaptable insulation is employed. It is constructed from a chemical combination that, when used, expands and solidifies into foam.

The high R-value of spray foam insulation creates an airtight seal, just like blown-in cellulose. It’s a great choice for cutting energy expenditures because of this. However, it costs more than other types of insulation and needs expert installation.

spray foam insulation

4. Rigid Foam Board Insulation

Polystyrene or polyurethane are the materials used in this form of insulation. It is a hard substance that is placed directly on the walls and serves as a reliable barrier against heat transmission. It can also be used as external solid wall insulation for the house.

Due to the high rate of heat loss from dwellings, rigid foam insulation is the best choice since it has a high R-value. However, compared to other forms of insulation, this one can be more expensive and needs to be put carefully to guarantee that it is done correctly.

Get A FREE Quote Now

Get a no obligation FREE quote now. Our team is here to help. Take the first step towards a guaranteed solution by filling out our form below. 

uk trademan

The Benefits and Drawbacks of Each Insulation Type

Several insulations are available for cavity walls, each with benefits and drawbacks. Here, we’ve taken a deeper look at the four most popular insulation materials for interior walls: rigid foam, spray foam, and fibreglass batts.

Fibreglass Batts

  • Advantages: Fiberglass batts are affordable, which makes them an attractive choice for budget-conscious homeowners. They have a high R-value, which makes them very good at keeping the heat in and lowering energy costs.
  • Disadvantages: One of the major drawbacks of fibreglass batts insulation is that it does not provide an airtight seal, allowing air to circulate through the walls and reducing its effectiveness.

Blown-in Cellulose

  • Advantages: Blown-in cellulose is also a popular choice for internal wall insulation. This type of solid wall insulation has a high R-value and provides an excellent air seal, effectively reducing energy costs.
  • Disadvantages: This insulation can settle over time, reducing its effectiveness. And you can’t use it over stone walls.

Spray Foam Insulation

  • Advantages: Spray foam insulation is a versatile option that can be used on internal walls as well as other areas of the home. It is also equipped with a high R-value and provides an airtight seal, making it an excellent option for reducing energy costs.
  • Disadvantages: The drawback of spray foam insulation is it can be more expensive than other types of insulation. 

Rigid Foam Board Insulation

  • Advantages: This insulation is also widely used for internal walls that require additional insulation due to a high rate of heat loss.
  • Disadvantages: It has a few disadvantages, the main one being that rigid insulation boards can be more expensive than other types. 

What Is The Best Insulation for Internal Walls?

Regarding insulating internal walls, fibreglass insulation is a popular choice among homeowners and builders. This insulation is made of fine glass fibres woven into a mat, then treated with a fire retardant. There are different reasons why fibreglass insulation is an excellent option for internal walls:

  • Cost-effective: Fiberglass insulation is one of the most affordable options available in the market. For that, it is an attractive choice for budget-conscious homeowners.
  • Easy to Install: Fiberglass insulation comes in pre-cut batts, making it easy to install even for those with limited DIY skills.
  • High R-value: Fiberglass insulation has a high R-value, which means it is effective at trapping heat in stud walls and reducing energy costs.
  • Versatile: Fiberglass insulation is suitable for use in different internal wall types, including those with electrical fixtures, plumbing, and ducts.

What Factors to Consider When Choosing Insulation for Internal Walls?

You’ll have to consider several factors when choosing insulation for internal walls. This is because these factors will impact the effectiveness and longevity of the insulation. Here are some key factors to keep in mind when making your decision:

  1. Cost: Cost is often one of the biggest factors when selecting insulation for internal walls. Different types of insulation have varying costs, so you should consider your budget when making your decision. Some options, such as fibreglass batts, are more affordable, while others, such as spray foam insulation, can be more expensive.
  2. R-value: The R-value of insulation helps to resist heat flow in the house. So, higher R-values mean better insulation and improved energy efficiency. When choosing insulation for internal or external walls, consider the R-value of the material so that it will effectively reduce energy costs and keep your home comfortable.
  3. Soundproofing: If you are concerned about noise levels in your home, soundproofing is a crucial factor when selecting insulation for internal walls. Certain types of insulation, such as spray foam insulation, are better at reducing sound transfer than others.
  4. Allergies and Health Concerns: Some types of insulation, like fibreglass batts, can irritate skin and eyes, and inhaling fibreglass particles can cause respiratory problems. Consider the materials less likely to cause allergies or respiratory sensitivities if you or a family member has either of these conditions.
  5. Moisture Resistance: Moisture can be a problem in internal walls, especially if the insulation becomes damp. Certain types of insulation, such as rigid foam, are more moisture-resistant than others, making them a better option for solid walls in humid climates.
What Is The Best Insulation For Internal Walls
Construction! Interior Walls!

Frequently Asked Questions

Here, we’ve arranged some frequently asked questions about internal wall insulation to help you make an informed decision.

1. How Much Does Internal Wall Insulation Cost?

The cost of internal wall insulation can vary depending on several factors. The factors include insulation material type, insulated area size, and labour cost. On average, internal cavity wall insulation may cost anywhere from $1 to $3 per square foot.

2. Does Internal Wall Insulation Work?

Yes, internal wall insulation is an energy-efficient way to reduce heating bills in a building. It creates a barrier between the interior of the building and the outside environment.

This keeps heat inside the building and reduces heat loss. Different types of internal wall insulation, like fibreglass batts, blown-in cellulose, rigid foam board, and spray foam insulation, each have unique properties and benefits.

3. Is Internal Wall Insulation a Good Idea?

Yes, internal wall insulation can be a wise decision for many homeowners. This can reduce heating bills and improve comfort by increasing the energy efficiency of a building.

Along with lowering heating costs, it decreases noise levels and enhances air quality by minimizing the amount of air infiltration. o if you’re making the decision to install internal wall insulation, you can be sure that it will benefit your home in many ways.

Get A FREE Quote Now

Get a no obligation FREE quote now. Our team is here to help. Take the first step towards a guaranteed solution by filling out our form below. 

uk trademan


From now on, you should know: What is the best insulation for internal walls? In general, fibreglass insulation is the best insulation for internal walls. Affordability and easy installation make this insulation the most popular choice. 

It is also very durable and will last for many years as well as keep energy bills low. Fibreglass insulation is also fire-resistant and environmentally friendly. However, you should consider your internal or external wall insulation type before making a decision. 

Useful links:

Picture of Jake Fitzgerald - Damp Surveyor

Jake Fitzgerald - Damp Surveyor

Surveyor of Timber & Dampness in Buildings (CSTDB) & ( MRICS ) Chartered Quantity Surveyor

Jake is a qualified chartered quantity surveyor and experienced damp specialist with a unique skill set in thermal imaging. With a focus on effective solutions, Jake combines his expertise in quantity surveying and thermal imaging to accurately assess and address damp-related issues. He utilises advanced technology to identify hidden moisture sources and develop targeted strategies, ensuring comprehensive and cost-effective solutions for his clients. With a commitment to open communication and client satisfaction, Jake delivers cutting-edge solutions that tackle damp challenges head-on.

Connect with him on Linkedin...

Related Posts

Table of Contents

Need advice?

Talk to one of our experts:

Contact us Now

0300 373 7251

Claim your free Ebook!

Learn how to diagnose and control damp yourself with our all-in-one guide

Fill out your email below to receive your free ebook...

Our Services

advanced damp proofing vans

Quick Form

Fill in the form below and we will be in touch soon

Find us on Facebook

Advanced Damp LTD

Meet Your Damp Experts at Advanced Damp

Welcome to Advanced Damp, where we bring over 30 years of professional expertise in damp treatments to homes and businesses across the nation.

🛡️ 20-Year Property Maintenance Guarantee: Every service we offer comes with the assurance of a 20-year property maintenance guarantee, reflecting our commitment to quality and long-term customer satisfaction.

🤝 Ready to Assist You: Our damp specialists are just a call away, ready to offer their expert advice and tailored solutions for your property. Whether it's a residential space or a commercial establishment, we're here to ensure your environment remains damp-free and healthy.

📞 Contact Us for Expert Damp Solutions: Don't let damp issues linger. Reach out to the Advanced Damp team today for effective treatments and peace of mind.

"We have located a local Specialist in your area"

Please fill out our short form below and describe the problem you are having. We will be in touch very shortly.

Call Us Now