Cellulose insulation is made primarily from recycled paper products, treated with fire-retardant and pest-resistant chemicals, making it one of the more environmentally friendly insulation choices available. It’s typically installed using a blown-in method, allowing it to settle into wall cavities, attics, and other irregular spaces more thoroughly than batt insulation, which can leave gaps around obstructions. This dense fill also provides excellent soundproofing, making it a popular choice for homeowners looking to reduce noise transfer between rooms or from outside. Cellulose performs well thermally and can be a cost-effective option for retrofitting older homes where walls are already closed up, since it can be blown in through small access holes without major demolition. Its density also helps reduce airflow through the insulated cavity, contributing to overall energy efficiency.