Can a different type of insulation be placed over an existing fiberglass insulation, already in place? I have only 12 inches of fiberglass insulation in my attic. A contractor said that I needed to place additional insulation to bring that up to 20 inches. Another contractor said that I could use cellulose over the fiberglass.
Question is? Is there any reason you can’t use a different type of insulation on top of the existing, such as cellulose? Or would I be best to keep consistent, and use the fiberglass insulation? Is weight a factor? Do I REALLY NEED 20 inches of insulation. I live in hot north central Texas.
Fiberglass seems to cost more, so cost is a factor as well. But, I also am concerned about cellulose becoming a fire hazzard. What are my best alternatives here?