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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.
What are the disadvantages of cellulose insulation?
Cons of Cellulose Insulation It generates a lot of dust during installation. It is heat-resistant and has a high R-value. Cellulose insulation is prone to sagging and settling. It is heavily treated with fire-retardant chemicals.
Is blown-in fiberglass cheaper than cellulose?
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.
What is best blown-in insulation?
Blown-in Insulation Fiberglass, cotton, and mineral wool can all work as loose-fill material, but the far and away top choice for blown-in insulation is fiberglass. Contrary to batts insulation, blown-in fiberglass insulation is perfect for filling in tight voids around wiring, pipes, or any area with awkward framing.
Is cellulose insulation good for attic?
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.
How long does blown in insulation last?
How Long Does Blown in Attic Insulation Last? Regardless of what kind of insulation you choose, blown insulation is a permanent solution. Cellulose insulation lasts 20-30 years because it is made from recycled natural materials, whereas fiberglass materials will last much longer because it does not degrade.
Can cellulose insulation be blown in 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”.
Does cellulose insulation break down?
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 lose R-value?
As a loose-fill insulation, cellulose provides high insulating values, represented by its higher R-value, and it creates a good barrier against air leaks and infiltration. However, like other loose fill insulation, it also has a tendency to settle over time, reducing its R-value and its ability to prevent air movement.
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.
Which is better attic insulation blown or rolled?
Rolled fiberglass insulation scores an R-value of 3.7. So overall, rolled fiberglass insulation is slightly more effective at blocking in and out heat than its blown counterpart.
What is the average price for blown-in cellulose insulation?
The cost to have blown-in cellulose insulation installed varies based on the type of cellulose necessary. On average, cellulose runs $1.20 per square foot to install, with wet-spray cellulose ranging from $0.60 to $1.80 per square foot and dense-pack cellulose running $2.00 to $2.30 per square foot.
Does cellulose insulation deter mice?
Cellulose insulation is a deterrent for mice and other types of pests. Pests prefer solid materials where they can burrow and nest. The dry composition of the insulation makes it difficult for most pests and mice to survive.
Does blown-in cellulose insulation contain asbestos?
A closer inspection indicates this gray puffy material has no minerals, but appears like gray shredded paper. This means cellulose insulation does not contain asbestos and is a safe insulation, blown into the cavities.
What happens if cellulose insulation gets wet?
When the fibers become wet to an excessive level, their weight increases, and the material will slowly compress and settle. The more your cellulose insulation compresses, the more it will expose parts of your wall or attic, greatly reducing the effectiveness of your insulation.
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.
Should you remove old attic insulation before adding new?
Expert contractors that specialize in insulation advise that removing old fiberglass insulation is best before installing new cellulose insulation because of possible mildew, mold, or rodent excrement. So, by have attic insulation removal service, you are getting rid of those possible issues.
Will blown insulation mold?
in general, blown-in cellulose insulation, surprisingly, is not found moldy.” Both fiberglass and rockwool insulation (inorganic materials) have been tested. In the rockwool insulation tests showed enough nutrients to keep mold spores alive, probably from dust in the mineral fibers.
Can you put too much insulation in your attic?
It’s possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.
Can you put fiberglass insulation over blown-in insulation?
A: There’s no problem with installing fiberglass batts over your existing blown-in insulation. The reason for this precaution is that the facing on the insulation batts is a vapor barrier, which is intended to prevent moisture vapor from penetrating into the insulation.
Does fiberglass insulation lose R-value over time?
Fiberglass Insulation Struggles to Release Moisture That’s because insulation performance decreases dramatically. A 1.5% increase in moisture content in fiberglass insulation can reduce its R-value by up to 50%, according to Rastra. That’s not a typo.