Get matched with top doorbell installation pros in Snowflake, AZ

Structural insulated panels and rigid foam boards have the highest R-value of any insulation that contractors commonly use, with R-values reaching up to around 8.0. These types of insulation are best in extremely cold climates, but they’re generally preferred for new construction, as they can be challenging to retrofit. Blown-in and loose fill insulation provide the next best insulative value, provided the installation is done properly. It’s important to choose an insulation type that meets your needs based on climate, as maximizing R-value may not always be financially worthwhile if you live in a moderate climate.

Rockwool insulation can last up to 100 years, but just how long this insulation lasts in your home depends on how well it's maintained. Poorly installed insulation may last only 30 years, so be sure to regularly inspect your home's insulation for water damage, settling, and pests to give your insulation the best chance of having a long lifespan.

On average, insulating an attic costs about $2,500, with a typical range of $1,500 to $3,500. The final price often depends on the attic's size, with costs generally falling between $1 to $3 per square foot. For example, insulating a 1,800-square-foot attic would likely cost between $1,800 and $5,400.

If the project involves removing old insulation, this can add an average of $900 to the total cost, bringing a full removal and reinsulation project to around $3,000.

Several factors influence the overall cost:

• Insulation Type: Prices per square foot vary significantly by material.

• Reflective: $0.50–$1.50

• Blown-in: $1–$4

• Batt: $2–$4

• Loose-fill: $2–$5

• Spray foam: $2–$5

• Structural insulated panels (SIPs): $4–$7

• Project Complexity: Factors like sealing air leaks, poor attic accessibility, and required inspections can add to the cost.

• Removal Issues: The discovery of mold, asbestos, or pests during the removal of old insulation can substantially increase the price.

If you plan on heating your garage, you must install a vapor barrier when drywalling the garage. A vapor barrier protects your garage from frost and mold that can occur through condensation. If your garage is unheated, you don't need to install a vapor barrier. The only exception is if you regularly crank the heat in your car before getting in it. In this case, you may still want to install a vapor barrier, as your car can heat your garage.