No, 55 degrees Fahrenheit is not too cold for a house, as it’s a temperature that will keep your pipes and appliances from freezing. Well-insulated homes can even go to 50 degrees, but check with an HVAC pro before opting for such a low temperature. Stick to 55 degrees to be on the safe side.

In some areas, insulation companies require a special license, while some states only require them to hold general contractor licenses. Some municipalities may not mandate any license, although you should always ensure a contractor is fully insured. You can use Angi’s license lookup tool to confirm whether or not an insulation contractor you’re considering holds the necessary license for your area. You can also contact the company for information regarding licenses, certifications, and insurance.

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.

Unless your cellulose insulation is wet, moldy, or showing signs of mildew or pests, there’s no need to remove it before adding new insulation on top of it. Inspect your insulation thoroughly before adding the new insulation, and if you’re unsure how to assess the presence of mold or mildew, talk to a mold remediation specialist near you.