On average, the cost of blown-in insulation ranges from $1.50 to $2.80 per square foot, leading to an average cost of blown-in insulation between $1,500 and $2,800 for a 1,000-square-foot area.
The cost to install blown-in insulation depends on the type of insulation you choose for the project. Anticipate spending anywhere between $0.50 and $2.30 per square foot for materials, not including installation.
For example, if the square footage of the room you're planning on insulating is 1,000 square feet and you want to achieve an R-value of 60, you will need approximately 17 bags to fully insulate your room. If you are using loose fill insulation, the coverage varies based on the R value that is needed.
Insulation levels are specified by R-Value. R-Value is a measure of insulation's ability to resist heat flow. The higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.
Mold and Mildew Growth
Having too much insulation in your attic can allow for the accumulation of moisture. This leads to mold and mildew growth, which can be extremely bad for your health.
Best Time of Year to Buy Insulation
In this case, the spring is the best time, because you will also start to see savings in the summer months. The same is true for warmer climates, just different times of year because you'll want the job finished before the heat sets in.
Budget: If you're working with a limited budget, blown-in cellulose might be the better option due to its lower installation cost. Energy Efficiency: If your priority is the highest possible energy efficiency, you may want to consider spray foam, particularly closed-cell foam.
Do I Have To Remove Old Insulation? Unless your insulation is wet, moldy or infested with pests, you don't need to remove it before adding insulation on top of it. ENERGY STAR® recommends that you inspect your insulation for signs of mold, mildew, moisture and pest infiltration before making this determination.
Blown fiberglass insulation scores an R-value of 3.2 to 3.8, making it slightly less likely than rolled fiberglass to prevent the flow of heat into and out of your house. That being said, though, blown fiberglass insulation isn't meant to cover huge areas like rolled fiberglass insulation.
Finishing an attic generally costs between $30 and $60 per square foot, including labor and materials. This gives you an average overall cost of $4,000 to $16,000 for the standard sized attic. Of course, the cost depends on how big your attic is and what type of finish you want.
Blown-In Insulation (Fiberglass And Cellulose)
In most homes, loose-fill insulation can survive anywhere from 80 to 100 years before needing replacement, provided that it is not damaged.
If the attic damage was caused by a covered risk, such as fire or wind, your home's insurance policy may pay the cost of rehabilitation. Repairing or replacing damaged insulation, drywall, and other materials could be included.
Fiberglass batt is considered to be the best insulation for attics. Compared to other insulation materials, it is the cheapest and easiest to install. Fiberglass batt is also incredibly energy efficient, as it helps to slow the spread of hot and cold air.
However, insulation can start falling from fiberglass batts after 15 to 20 years, so if your insulation was installed in batts well over a decade ago, it might be time for an inspection or a home energy audit.
On average, insulation costs are nearly 25% higher than they were in Q3 of 2022. A primary reason for the increase is rising insulation input prices, particularly mineral wool, which have climbed for two years and show no signs of regression.
When blown-in insulation settles, your attic loses insulation performance. Settling compromises the R-value of your insulation.
Cons of Blown-In Attic Insulation:
Poor installation can lead to uneven coverage, material waste, and even structural issues like sagging ceilings. Hiring a skilled installer is crucial to getting the most out of this insulation type.
Also, when laying down additional insulation, work from the perimeter toward the attic opening. Never lay insulation over recessed light fixtures or soffit vents. Keep all insulation at least 3 inches away from recessed "can" lights, unless they are rated IC (Insulated Ceiling).
How thick should blow-in insulation be in an attic? For attics, you should aim for an R-value between 38 and 49, depending on your specific needs and climate zone. To achieve an R-value of 38 to 49 in your attic, you should aim to install 11 to 14 inches of blow-in cellulose insulation.
On average, attic insulation costs $1 to $3 per square foot, so for a 1,800-square-foot attic, you'd pay $1,800 to $5,400, including materials and labor.
The average cost of blown-in insulation using cellulose ranges from $0.60 to $2.30 per square foot. In colder climates, cellulose's higher density provides better insulation against heat loss, improving energy efficiency.