Some Disadvantages of Cellulose Insulation You Should Know

A popular choice among homeowners for home insulation is cellulose insulation, a type of loose-fill cellulose insulation. This insulation material is made from recycled paper products like old newspapers and cardboard, in wet and dry forms.

Wet cellulose insulation is blown in when the cellulose is slightly damp, whereas dry cellulose insulation is blown in while the material is dry. Despite the many benefits it provides, cellulose insulation also has disadvantages.

Cellulose Insulation Problems

  1. It Will Settle Up Eventually

Cellulose insulation’s pros and cons include the issue of settling. Modern cellulose insulation, often made of recycled cellulose fiber and treated with fire retardant chemicals like boric acid, can settle up to 20%. This process, known as bridging, occurs when the cellulose in wall cavities separates over time, creating gaps.

When this occurs, the holes enable air to flow in and out of the house, resulting in high monthly energy bills as your mechanicals work overtime to maintain a consistent temperature. If your home has loose-fill cellulose, pests will shift it about to make a nest, resulting in a rodent mess and significant gaps in insulation coverage.

  1. It Spreads Dust

Another disadvantage of cellulose insulation is that densely packed cellulose may be found almost anywhere at your house. Any gaps in the wall cavities, such as electrical outlets, might allow dense-packed cellulose insulation to leak into the house.

disadvantages of cellulose insulation

Some cellulose dust will be recirculated throughout the house in homes with furnace duct systems. It’s the same with loose-fill insulation. The dust in the material kicks up and makes its way into the ducts in the home as it is blown or shifted about.

Read also: Here’s How to Keep a Poorly Insulated House Warm

  1. Lack of Experts and Unpopular Building Codes

It can be difficult to find installers familiar with cellulose in some places. An expert installer knows how to dense-pack loose-fill dry cellulose appropriately, apply stabilized (partially wet) cellulose on sloped surfaces, and how long wet-spray cellulose takes to dry.

Building codes in the United States may not be updated for cellulose insulation, as they are for other non-batt insulation. Homeowners should contact the city to confirm that the insulation will be approved, and the city may require product specifications.

This is not a difficult task; both the installer and the manufacturer should be willing to take care of it, saving the homeowner time and effort.

  1. It is Heavier than Other Insulation

Loose cellulose weighs nearly three times as much per square foot as loose fiberglass for the same R-value. Before choosing a material to insulate the ceilings of existing structures, they should be evaluated for indicators of fragility.

Does Cellulose Insulation Cause Any Dangers?

Cellulose insulation, particularly when not properly installed, will likely generate excessive dust. This can be exacerbated in cases where the cellulose fiber is not adequately treated with fire retardant agents like boric acid, leading to potential safety concerns.

This is particularly common in regularly used areas and can be a serious health hazard, especially if you live in a carpet-free house where dust can stay airborne for longer.

Even though it has generated a dust problem, there are no risks of very fine fibers entering your breathing system or creating long-term damage if inhaled. This is true of alternate goods like fiberglass insulation but not cellulose.

Overall Pros And Cons Of Cellulose Insulation

Some of the advantages of using cellulose insulation are as follows: First, a paper-hungry civilization generates mountains of discarded paper and cardboard, which cellulose insulation helps to minimize.

Secondly, cellulose’s R-value is higher than ordinary fiberglass (approximately R-3.2 per inch) (R-2.2 per inch).

Also, the health concerns associated with cellulose are significantly lower than those associated with fiberglass. Lastly, the most favorite advantage is that cellulose insulation is often less expensive than fiberglass insulation (up to 25 percent cheaper, in some cases).

While the disadvantages of cellulose insulation experienced by some housebuilders are :

First, when cellulose insulation is put, it generates a tremendous amount of dust. Hence an approved breathing mask is required.

Secondly, cellulose insulation readily absorbs moisture, reducing its long-term efficiency and perhaps causing mold and decay.

These effects can even be seen in wet-blown cellulose. Also, a vapor barrier is required for both dry and wet-blown cellulose, and the cost of installing cellulose can be higher than installing fiberglass.

Installing cellulose insulation requires expertise, as improper installation can lead to issues like moisture absorption, reducing its efficiency over a long time. Despite these drawbacks, cellulose insulation remains a popular insulation product due to its environmental benefits and cost-effectiveness compared to other types of insulation like fiberglass.

Energy Efficiency and Moisture Concerns in Cellulose Insulation

Another aspect to consider is the energy efficiency of cellulose insulation. While it offers good thermal resistance, its tendency to settle over time can reduce its effectiveness. Homeowners looking for long-term, energy-efficient solutions might find this a significant drawback.

Additionally, in cases of water damage, cellulose insulation can absorb moisture, reducing its insulating properties and posing a risk of mold growth.


In conclusion, while cellulose insulation has advantages, such as being environmentally friendly and cost-effective, it also has several disadvantages. These include the potential for settling, dust generation, moisture absorption, and the need for fire retardant treatment.

Homeowners should weigh these factors carefully when choosing insulation products for their homes.

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Insulator is a skilled author and Insulation expert with years of experience in the field. He has authored several articles and books on various aspects of insulation installation, maintenance, and repair.