Comparing Cellulose and Fiberglass Insulation for Your Attic

Close Up,of,strips,of,pink,fiberglass,insulation,in,a,wallWhen it comes to insulating your attic, two popular options are cellulose and fiberglass insulation. Both materials have their advantages and considerations, and understanding the differences between them can help you make an informed decision. In this blog, we will compare cellulose and fiberglass insulation, examining factors such as their installation, effectiveness, cost, and environmental impact.

1. Installation process:

Cellulose insulation is made from recycled paper products and is typically blown or sprayed into the attic using specialized equipment. It fills in gaps and conforms well to irregular spaces, providing excellent coverage. However, proper installation requires a professional with experience in handling the blowing equipment.

On the other hand, fiberglass insulation consists of fine glass fibers that come in pre-cut batts or rolls. It is relatively easy to handle and can be installed by homeowners themselves. Simply unroll the batts or rolls and fit them between the attic joists, making sure to wear protective gear to avoid skin irritation from the fibers.

2. Insulation effectiveness:

Both cellulose and fiberglass insulation are effective at reducing heat transfer and improving energy efficiency in your home. However, cellulose insulation has slightly higher insulating properties, mainly due to its ability to fill in small cracks and gaps more effectively. This can result in better thermal performance and reduced drafts in the attic.

Furthermore, cellulose insulation has a higher R-value per inch compared to fiberglass. R-value is the measure of insulation’s thermal resistance, with higher values indicating better insulation. This means that cellulose insulation can provide the same level of insulation with less material, making it a more space-efficient option.

3. Cost considerations:

When it comes to cost, fiberglass insulation tends to be the more affordable option. It is widely available and often comes at a lower price per square foot compared to cellulose insulation. This can make a significant difference, especially for larger attic spaces.

However, it is important to consider long-term savings when making a cost comparison. The energy savings achieved through proper insulation can help offset the initial investment over time. Additionally, considering the insulation’s lifespan and effectiveness can contribute to making a more cost-effective choice.

4. Environmental impact:

Cellulose insulation is often touted as an eco-friendly option due to its high recycled content. Made from shredded newspapers and other recycled paper products, cellulose insulation helps reduce landfill waste and promotes sustainable practices. Furthermore, cellulose is treated with fire-retardant chemicals, ensuring its safety and durability.

While fiberglass insulation does not contain recycled materials, some manufacturers offer options with a higher percentage of recycled content. Fiberglass insulation is non-combustible and does not require fire-retardant treatment. However, the manufacturing process for fiberglass does involve the use of energy and resources.

It is important to note that both cellulose and fiberglass insulation meet industry standards for safety and emissions. Additionally, proper installation and maintenance of insulation play a significant role in minimizing any potential environmental impact.

5. Considerations for other factors:

When choosing between cellulose and fiberglass insulation, there are a few additional factors to consider. For example, if your attic has existing insulation that needs to be topped up, cellulose insulation can be blown on top of the existing insulation more easily compared to fiberglass batts.

Furthermore, if you have concerns about pests such as rodents or insects in your attic, cellulose insulation may be a more suitable choice. Cellulose is denser and less appealing to pests, making it more resistant to infestations.


Both cellulose and fiberglass insulation have their merits, and the choice between them depends on your specific needs, budget, and environmental considerations. While cellulose insulation provides better coverage and thermal performance, fiberglass insulation is more cost-effective and easier to install. Considering these factors, as well as any other unique aspects of your attic space, will help you make an informed decision on the best insulation option for your home.

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