Cellulose insulation is a smart alternative to fiberglass. It provides a green, efficient, non-toxic, affordable thermal solution that’s worth considering.

Is cellulose good for attic insulation?

Cellulose — recycled, ground-up paper with boric acid added for insect control and fire resistance — offers a better attic insulation option than batts. … Cellulose provides an R-value of approximately 3.5 per inch. While it doesn’t actually create an air barrier, the dense material stops most air movement.

What are the dangers of cellulose insulation?

If you use loose-fill cellulose insulation on the attic floor, the airflow from the vents will cause the material to drift, leaving spaces in the attic uninsulated. Also, as that outside air moves through the cellulose, pollen, bacteria, and mold spores can cling to it.

What is the safest attic insulation?

• Cork. When it comes to healthy insulation, cork tops the list, at least according to a report done by Energy Efficiency For All. …
• FIberglass. …
• Cellulose. …
• Recycled Cotton. …
• Sheep’s Wool.

Why cellulose insulation is bad?

Cellulose insulation is treated with fire retardants such as ammonium sulfate, borax, and boric acid to meet all governmental safety requirements. … Unsurprisingly, this causes cellulose to have a higher fire rating than faced fiberglass insulation.

What are the benefits of cellulose insulation?

• Cellulose is made of recycled materials. …
• The R-value of cellulose is better than most other insulations. …
• It’s better for your health. …
• Cellulose is generally cheaper than many other options. …
• There are less risk of fires, mold and insects.

Which insulation is better fiberglass or cellulose?

At 3.5 per inch of material, the R-value of blown-in cellulose is 23% better per inch than fiberglass batts! According to research done at the Oak Ridge National Lab, fiberglass loses up to 50% of its R-value in very cold conditions; making cellulose a better choice for homes in northern climates.

How long does blown in cellulose insulation last?

Because it is made primarily of recycled materials, however, cellulose insulation does degrade over time. The typical lifespan is 20 to 30 years, with degradation beginning as early as 15 years after installation. As with other types of insulation, severe weather or outside interference can reduce the lifespan.

Does cellulose insulation need vapor barrier?

In summary, we do not recommend the use of vapor barriers with cellulose insulation, except in circumstances of exceptionally high moisture levels, such as an indoor pool facility, and we warrant our cellulose insulation for the life of the building when installed by an approved GreenFiber insulation contractor.

What happens if cellulose insulation gets wet?

How Water Inundation Impacts Cellulose Insulation. Cellulose is a loose-fill product. The material is designed to fill space with the “fluff” of the fibers to prevent voids and air pockets. When the fibers become wet to an excessive level, their weight increases, and the material will slowly compress and settle.

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Is it OK to put cellulose insulation over fiberglass?

No. Even if you have moisture in your attic, once all bypasses are sealed (and/or your roof repaired by a qualified contractor, if necessary) cellulose is blown directly over the existing insulation. … Adding new cellulose insulation on top of existing fiberglass insulation is called “capping”.

How thick should cellulose insulation be in attic?

The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.

What is the safest ceiling insulation?

Glasswool and rockwool insulation products are not hazardous products and are safe to install and use in your home or in other insulation applications for the life of the building.

What is the most eco-friendly insulation?

Cellulose. Considered one of the most eco-friendly types of insulation on the market, cellulose is made of up to 85 percent recycled content (mostly newspaper) and, like denim, uses a minimal amount of energy to produce.

Can cellulose insulation cause mold?

Mold growth sets in: Thanks to its chemical treatment, mold doesn’t grow on cellulose insulation. However, water-soaked fibers sit right against wood studs and drywall, which are susceptible to mold growth.

Do mice like cellulose insulation?

The insulation has a low toxicity to mammals such as mice that filter out the poison through their livers, Ansley says. But because the cellulose insulation is loose and falls in on itself, rodents don’t like it and will often leave because they prefer areas where they can burrow in order to nest.

Does cellulose insulation contain formaldehyde?

Cellulose insulation contains no harmful products such as those found in other types of insulation, including asbestos, fiberglass, ammonium sulfate and formaldehyde.

Should I remove old cellulose insulation?

Your insulation needs to be removed along with the droppings, as it’ll carry some of its toxicity if left in your attic. Removing old insulation and replacing it with new ones will not only rid your home from any rodent infestation and mold, but also improve its energy efficiency and overall air quality.

Which insulation is best for attic?

Many people consider fiberglass batt to be the best attic insulation. It consists of plastic reinforced by small glass fibers. The batt version comes in blanket form — i.e., small, pre-cut sections that you can lay down wherever you need to.

What is the R value of blown-in cellulose insulation?

Cellulose is an alternative to blown-in fiberglass. It’s a fiber made from around 80 to 85 percent recycled paper. Cellulose is denser than blown-in fiberglass, so it has a better R-value — about 3.2 to 3.8 per inch, however, it does settle and flatten over time, losing some of that insulating value.

Is cellulose insulation rodent resistant?

Cellulose insulation is made of recycled, ground-up paper. It has boric acid added to it to control and keep out insects and other pests. It’s also fire-resistant. Rodents generally are not drawn to cellulose insulation, either.

Is cellulose insulation more expensive than fiberglass?

When comparing blown-in insulation, both fiberglass and cellulose are nearly identical in price, both costing around $0.70 to $0.80 per square foot for 6 inches of insulation. Fiberglass batts, however, are less expensive, costing on average $0.30 to $0.40 a square foot for 6 inches of insulation.

Is cellulose insulation itchy?

Cellulose insulation is not itchy. However, individuals with pre-existing skin conditions are usually allergic to cellulose. If you have any skin irritation, it is best to stay away from cellulose insulation.

What are the disadvantages of cellulose?

Disadvantages. Installation costs for cellulose can be higher than for fiberglass. Cellulose insulation creates an enormous amount of dust when it is installed, so a certified breathing mask is absolutely essential. Dry-blown cellulose sags and settles, reducing its R-value over time.

What are the advantages and disadvantages of cellulose?

• Versatile and can be combined with spray foam insulation.
• Treated to be fire retardant.
• Cost-effective.
• Similar R-Value to fiberglass insulation.
• Environmentally friendly due to high levels of recycled content.
• Allows for dense packing in existing wall cavities.

How long has cellulose insulation been around?

The 1950s – 1970s Another form of insulation that became popular is cellulose. Made of newspaper, cardboard, straw, sawdust, or cotton, cellulose was actually one of the earliest types of insulation.

Is dense pack cellulose an air barrier?

Dense pack cellulose and dense pack fiberglass are not air barrier materials, and they do not result in air barrier assemblies. Although, with respect to air barrier assemblies, they sometimes come pretty close.

Why is there no vapor barrier in the attic?

The theory is that part of the moisture vapor in the house is actually blocked by the drywall and paint on the ceiling. … If you don’t remove the vapor barrier, you run the risk of trapping moisture vapor that passes through the loose fill against the vapor barrier, where it can’t escape from the attic.

How do you tell if your attic is properly insulated?

While you’re at it, feel the ceiling and see if it seems strangely hot or cold in any area. If any rooms have odd temperature changes, there’s a good chance that the insulation in that area is poor and will need to be replaced. Note that ceilings aren’t the only areas where insulation can be poor.

Can I put new insulation over old?

According to ENERGY STAR®, you can put new insulation over old insulation, “unless it is wet. … The vapor retarder on top of or between layers of insulation can trap moisture. Any existing batt or roll insulation in the attic should have the facing against the attic drywall floor or no facing at all.

Is blown in insulation worth it?

Unless your home is relatively new, you will almost certainly benefit from installing blown insulation in your attic. It will make your home a more comfortable place to be in summer and winter, decrease the cost of your energy bills, and increase the value of your home.