Fiberglass Insulation vs Cellulose Insulation

Upgrade your home.

Home insulation is utmost importance when it comes to energy saving. With the proper design and install of an insulation system, need for energy will be reduced, resulting in lower bills. The best insulation systems such Spray Foam, Fiberglass and Cellulose can reduce your energy bills up to 30%. When insulating your living area, you are also protecting your home from caustic pollution. Insulation systems can be great choices if you are looking to reduce sounds from outside or inside the house.

Many insulation methods have insecticidal and preservation properties also. Whether fiberglass, spray foam or cellulose, these materials will keep your walls always untouched.

All of the above-mentioned factors will make your home a more comfortable and valuable place. There are no right or wrong choices when it comes to insulation. You can choose from a variety of methods and materials to ensure you are installing the proper insulation system your home requires.

Though there are a few insulation methods that are highlighted from the others, as they meet the R-Value requirements and fulfill the home insulation needs.

Before you make a decision make sure to weigh the pros and cons of each method to ensure you are making the right choice for you and your home.

Below you will see a comparison table of some of the most commonly used insulation methods.

Properties (rating)

Fiberglass Insulation

Spray Foam Insulation

Cellulose Insulation

R-Value (per inch of Thickness) R-2.2 up to R-4.3 R-3.7 up to R-6.5 R-3.1 up to R-3.7
Durability 25 – 50 years 80 – 100 years 80 – 100 years
Reduce of energy bills (by) 20% 40% 25%
Payback Time 3 – 4 years 2 – 3 years 3 – 4 years









Advantages and disadvantages of most common insulation systems

Spray Foam Insulation


-High R-Value

-Sound absorption properties

-Mold resistant


-Insect Repellent

-Retains its insulation properties


-Costs more than traditional insulation options

-Only a professional of the field can do the installation


Fiberglass Insulation


-Sound absorption properties

-Insect Repellent

-Low insulation cost

-High volume of recycled content

-Easy to install


-Prone to moisture

– Degrades when wet

-Insulation system might deteriorate if not maintained


Cellulose Insulation


-Fire resistant

-Creates a natural sound barrier

-Insect Repellent


-High volume of recycled content


– Dry-blown cellulose sags and settles, reducing its R-value over time.

-Has a higher installation cost than fiberglass

– Might deteriorate if not maintained

Fiberglass and Cellulose Secret Ingredient

For insulation purposes cellulose material is treated with boric acid. Boric acid is one of the most commonly used substances that can counteract with fiberglass and cellulose materials. Boric acid prevents mold from getting into the wall and also makes the cellulose fire resistant.

Same method is used with fiberglass. Whether glass fiber, rock wool or natural materials, they will be treated with boric acid in order to make them better insulation materials.

Boric acid has insecticidal and preservation properties. The insulation materials treated with boric acid will keep the insulated perimeter clear from insects and mold. It is considered to be safe to use in house environments such as home walls, basement, garage, floor and ceilings.

Sound Insulation

Best types of insulation for sound control are fiberglass, cellulose and spray foam insulation. These methods can be great choices if you are looking to reduce noise coming from outside of the house and between rooms or levels inside your house. These materials have the ability to muffle sounds from the street or from one room to another.

There is no doubt that insulation will make your home a much quieter place, but which insulation method has the best sound efficient properties?

Spray Foam claims the first place due to better sound reduction capabilities compared with other insulation methods. It has the ability to create a noise proof environment by filling the applicable area with impenetrable foam. Cellulose insulation is also highly recommended from home builders. Its installation model which compresses cellulose into the wall space creates a dense obstacle who serves as a sound barrier.

Go natural

To lower the negative environmental impact, many home builders and home owners choose eco- friendly insulation alternatives. Whether fiberglass or cellulose, these products have a high percentage of natural fiber. Fiberglass batts are made of recycled glass. You can also choose batts made of sheep’s wool, cotton or straw. As per cellulose insulation its main product is recycled paper, such as newspaper or phone books. Being recycled materials, fiberglass batts and cellulose need minimal energy to be manufactured. For insulation purposes, these materials are treated to adapt with R-Value requirements.


Product Recycled material Recycled percentage Merged material
Glass fiber Molten glass 40% up to 60% Sand, limestone, soda ash, mineral borate
Sheep’s wool Sheep’s wool 85% Mineral borate
Straw Straw 80% Kraft paper
Cotton Cotton 85% Plastic fibers
Mineral wool Rock and molten metal 75%
Cellulose Newspapers, phone books, cardboard 82% up to 85% Mineral borate

Long-term Cost Savings

How much can you forecast to save in costs? It depends.

Annual savings from insulation systems rely on many factors, including: heating and cooling use, original wall performance, insulation thickness, local climate, and more.

Local climate

To be more precise, if you are living in a cold place, you will spend more energy on heating and therefore the savings on energy bills will be higher than a home insulated in a warmer area.

Heating and cooling use

Home builders highly recommend big energy consumers to insulate their properties. Big houses or workplaces for example require more energy to maintain the appropriate temperature throughout the year. The insulation system capabilities will be more cost efficient in these cases.

Original wall performance


Stone wall

Wooden wall



Thermal Resistance Coefficient









Prior insulation process, inspect the walls that will be insulated for cracks and bulges. It there is any, you will have to close them to avoid any air flow. Insulation system performance is also very dependable in wall material.

Surprisingly, straw and wooden walls are more resistant to heat flow compared with stone and loess made walls. This happens due to the gaps generated from the masonry process.

Insulation thickness

It is understandable that as the insulation thickness increases, consequently the heat flow decreases. There is no such thing as too much insulation. But yes, the insulation materials come with a cost. The ideal insulation thickness is the one who exceeds the R-Value requirements at the lowest cost.

Why Solve?

Solve’s insulation team strives to provide the best quality products and the highest standard of expertise.

Our professionalism and experience goal is that you never have to worry about anything less than thorough and complete workmanship. Our professionals will guide you through the consultation to the execution stage. With our extensive experience on Fiberglass and Cellulose Insulation, we can guide you to pick the best option for your space.