Best Insulation for 2×4 Walls – Buyer’s Guide

by James Antony | Last Updated: 26th February 2020

If you’re going to insulate 2×4 walls, it is important to know what the appropriate thickness should be. The question is all the more critical when one considers that these assemblies and insulations are permanent. This is because once the walls are insulated and sealed up, it is not an easy task to change them out.

Too little – or too much – insulation leads to a colder house than is necessary. The air pockets within the insulation are what work to keep a home warm, not the fiberglass. It is essential then to get a fine balance between too little and too much insulation to keep your family warm during the winter period.

Another important feature to consider when selecting the best insulation for 2×4 walls is the sound dampening capabilities. This is an essential component when maintaining calm and peace inside the house by dampening the noise.

Owens Corning R-13 Faced Insulation Roll Review - Best Insulation for 2x4 Walls

Many of the products available in the market also ensure that they are water-resistant, which ensures that there is no danger of mold or mildew growth. This ensures that the air quality of the house is maintained.

There are hundreds of products available in the market that can really make the buying process an ordeal in itself. That is why, in order to make the process a little easier, in this article, we take a look at three different products that are perfect when it comes to providing the ideal thermal insulation to your house.

Of course, you can change the R-value of the product depending on where you live and get a roll that is suited to your climate.

Owens Corning R-13 Faced Insulation RollBest Construction

Owens Corning R-13 Faced Insulation Roll Review - Best Insulation for 2x4 Walls

Owens Corning R-13 Faced Insulation Roll


Owens Corning is known to produce one of the most effective insulations for 2×4 walls. Its insulation rolls improve the comfort of your home by ensuring thermal control and noise reduction. The company has a strong reputation for providing a performance that is trusted by homebuilders.


The insulation roll is easy to apply and soft to the touch. It also contains less dust than other fiberglass insulation products.

Material Design and R-value range

The products are made with 100% renewable energy and are free of formaldehyde. It is pre-formed blanket insulation, which is quite flexible. The R-values that you can get from these rolls are between 11 and 49. The higher the value, the greater the insulating power.

Its thickness can range between 3.5 to 14 inches giving an ample choice for people living in different climes.

Owens Corning R-13 Faced Insulation Roll Review - Best Insulation for 2x4 Walls


The Fiberglass insulation keeps your home warm and ensures that it is quiet and comfortable, giving you full thermal and acoustic control. Users don’t have to worry about how the air quality is going to be as the product ensures that it meets the high standards for indoor air quality maintained by GREENGUARD.

  • Made with wind-powered electricity
  • Soft and easy to install
  • Maintains high standards of air quality
  • Available in multiple R-values
  • Free of formaldehyde
  • Has less dust than other fiberglass insulators
  • A little on the expensive side

JOHNS MANVILLE INTL 90013166 Series R13 15”x32” Kraft RollBest Vapor Control

JOHNS MANVILLE INTL 90013166 Series R13 15”x32” Kraft Roll Review - Best Insulation for 2x4 Walls

JOHNS MANVILLE INTL 15”x32” Kraft Roll


John Manville has been in the business of developing and manufacturing building materials for almost 160 years. This fiberglass roll insulation is a testament to the ingenuity of their product design that delivers high performance every time.


The fiberglass can be installed with minimal effort and equipment. By following the instructions provided with the product, anyone can easily install the roll in floors, ceilings, 2×4 walls, attics, and around objects.


The fiberglass insulation is formaldehyde-free, made with recycled glass, and helps reduce energy expenditure on cooling and heating. Furthermore, it is also quite friendly to those suffering from allergies and asthma.

JOHNS MANVILLE INTL 90013166 Series R13 15”x32” Kraft Roll Review - Best Insulation for 2x4 Walls


The roll works extremely well to insulate large spaces with little obstructions such as an attic or a basement. At the same time, it can also be used to fit in wall cavities. Users also have the option of getting a Kraft-faced vapor retarder that meets the codes where vapor control is necessary.

Insulating the ceiling and floor may not seem like an important thing, but it can greatly protect the floor from cold basements and also reduce the noise from above.

The product is GREENGUARD Gold certified and ensures that high air quality levels are maintained. It is also Energy Star Certified, which means that it keeps your house energy efficient.

  • Easy to install
  • Provides amazing moisture control
  • Can be applied in floors, ceilings, walls, and around objects
  • Environment-friendly construction
  • Helps reduce energy expenditure
  • No warranty

Rockwool Acoustic Mineral Wool Insulation 80-8lb 48”x24”x2”Best Soundproofing Material

Rockwool Acoustic Mineral Wool Insulation 80-8lb 48”x24”x2” Review - Best Insulation for 2x4 Walls

Rockwool Acoustic Mineral Wool Insulation


If you’re looking for noise and thermal barriers for 2×4 walls, you can never go wrong with Roxul. The company is a highly reliable manufacturer of top-quality soundproofing material. Here too, it has come up with a product that will satisfy multiple customer needs.


Roxul Rockwool is ideal for blocking noise in rooms where both thermal insulation and acoustics are a priority. Though it has a lower sound-absorbing performance when it comes to the lower frequencies, the thermal insulation capabilities are quite high.

The thicker the panels, the better the performance one can expect when it comes to dampening the low-frequency levels.

Therefore, if you want to curb the deeper, bass-heavy noises from reaching other rooms, a 4-inch think panel is recommended. It is also a highly water-repelling product and holds up well against mold and mildew, thereby ensuring that the air quality of your house remains ideally high.

The fact that the product is fire-resistant is generally overlooked but is definitely a major plus point, especially when considering the safety of its use.


With a few basic instructions, anyone can apply these boards to the walls. No special tools are needed. With a butter knife, you can easily cut the parts according to your needs. It can be used on the inside of exterior walls and on top of thermal regulation insulation to soundproof them.

It can also be applied to the ceiling and the floors to ensure better acoustics and block unwanted noises. If you are a musician or have a budding musician in your house, this product will work like a charm as sound-absorbing material for home studios and ensure that other members of the household are not disturbed.

  • Amazing sound dampening capabilities
  • Easy installation
  • Is water-resistant and holds well against mold
  • Is fire-resistant
  • Ensures high air quality
  • Can be applied to walls, floor, and ceilings
  • High value for money
  • May require thicker panels for effective thermal insulation

JOHNS MANVILLE INTL 90013166 Series R13 15”x32” Kraft Roll Review - Best Insulation for 2x4 Walls

Best Insulation for 2×4 Walls – FAQs

What is R-value?

An R-value identifies insulation wherein the ‘R’ stands for resistance to heat flow. The higher the value, the better the insulating power.

How much insulation is needed for 2×4 walls?

The modern 2×4 walls have a cavity depth of three and a half inches. Therefore, it is best to stick with an R-value between 13 and 15 of fiberglass insulation.

What is the most eco-friendly insulation?

The most environmentally friendly insulation material is cellulose insulation. It is made of 80 – 85% recycled newsprint.

What is the cheapest insulation?

The cheapest insulation is fiberglass batts. However, any loose tear can greatly diminish the quality of insulation.

Where should insulation be installed?

Insulation should not only be limited to outer walls and attics. For a thoroughly insulated home, it is best to install insulation in as many areas as possible. These include ceilings, floors, basements walls, interior walls, floors above vented crawl space, around perimeters of a slab, and sloped walls.

What are some things to consider when choosing insulation?

There are various things to consider, such as thermal performance, fire safety, resistance to moisture, permanence, and resistance to settling. Most good products do well in all these aspects and ensure that users get the best out of their product of choice.

Best Insulation for 2×4 Walls – Final Thoughts

Ensure that the R-value of the product that you get is ideal for where you live. For insulating 2×4 walls, the recommended R-value is between 13 and 15. You can easily calculate the ideal R-value for other areas such as the attic, floors, and crawl spaces depending on where you live with the R-value chart that is provided by the U.S. Department of Energy.

We hope that through this article, you now have sufficient information to make a decision. Though there is a huge market for insulating rolls with major competition coming from new companies. There are only a handful of manufacturers that have truly understood the art of developing a product that can satisfy the multiple needs of the customers.

Of the industry giants, the three mentioned in our article have been tried and tested by thousands of homeowners and developers. Their products come highly recommended by professionals, and our own review has allowed us to delve deep into what makes them perfect for 2×4 wall insulation.

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