Attic Insulation Cost per Square Foot for Three Different Types of Material

Installing proper attic insulation will provide energy-saving benefits, besides the primary function of preventing heat from escaping the house during winter or for the heat to come in during summer.

Improper insulation system will cause your ventilation, heating, and air conditioning systems to be work harder than they supposed to. If you’re interested in setting one, read about the attic insulation cost per square foot below.

attic insulation cost per square foot

Attic Insulation Cost Per Square Foot

There are few options when it comes to attic insulation installment. You may learn about the cost of insulation per square foot in the attic depending on the types and their R-value, which is the rating system to measure certain material performance to resist health flow conduction in the following.

Note that the higher the R-value is, the more effective the attic insulation type works.

1. Batt insulation

This suits best if your attic has standard joists spacing. The batt attic insulation per square foot cost about $0.6 to $0.14.

The system is comprised of lengthy insulation fibers that are combined by using reflective foil or paper support. These fibers can be made from cellulose, fiberglass, cotton, or mineral wool materials.

Batt insulation cost

Batt insulation is ideal to use in a spacious room, but it may not suit as well for awkward-shaped and tight spaces, no matter what the material is. The insulation needs to be tailored perfectly to fit the frame and the electrical junction box to avoid any void.


  • Cellulose: 3.7-3.8
  • Cotton: 3.7-3.8
  • Mineral wool: 3.0-3.3
  • Fiberglass: 2.9-4.3

2. Loose-fill insulation

Also known as blown-in insulation, this system is best used in space with irregular joists’ obstruction or framing and aged attic that already insulated. The cost of blown-in attic insulation per square foot is $1 to $1.5.

You may purchase the loose-fill material sold in large bags and comprise small pieces of fiberglass, cellulose, or mineral wool. These materials need to be installed using a blowing machine. Similar to batt insulation, the R-values of blown-in attic insulation is also vary depending on the material and installation thickness.


  • Mineral wool: 3.0-3.3
  • Cellulose: 3.2-3.8
  • Fiberglass: 2.2-2.7

3. Spray Foam

Spray foam attic insulation is an ideal option if you want to redeem noise, use it on outdoor space, or new building construction. It sticks well to various surfaces as the material is sprayed on, making it the easiest to install.

Spray Foam cost

Amongst the three types listed, this is the priciest one. However, there are two open and closed cells, and the earlier option is more affordable than the latter, even though open cells cannot offer a vapor barrier. The closed-cell has a more dense quality and can provide a great barrier for water and air.

R-value/inch: 5.0-6.0

It is important to learn about the material types and cost of an attic insulation project before calling a professional to handle it. The attic insulation cost per square foot ranges from $0.6 to $3.0, and the total cost might be anywhere from $1,500 to $2,500, depending on your space size and material choice.

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