Insulation
Insulation is material or a system that reduces or prevents the transfer of heat, sound, or electricity, primarily by creating a barrier, with common uses in buildings to lower energy costs and improve comfort (thermal insulation), or for soundproofing (acoustic insulation). Key types include fiberglass, mineral wool, foam boards, and cellulose, valued for their ability to resist heat flow (R-value) or block sound, improving energy efficiency and creating quieter, more comfortable spaces by keeping heat in during winter and out during summer.