The most common types of materials used for loose-fill insulation include cellulose, fiberglass, and mineral (rock or slag) wool. All of these materials are produced using recycled waste materials. Cellulose is primarily made from recycled newsprint. Most fiberglass products contain 40% to 60% recycled glass.

While insulation is easiest to add to new construction, it is possible to add it to an existing room as well. Insulating a room costs on average $650 to $1,000, with the average homeowner spending around $825 on adding blown-in insulation to existing walls and ceiling in a 10'x10' room.

Insulation helps increase the energy efficiency of home by reducing the amount of heat that escapes from it in the winter (containing the heat and keeping the house warm) and keeping it from getting too warm in the summer months (retaining the cold air and keeping the interior comfortable).