Spray foam insulation, particularly the open-cell variety, is highly effective for soundproofing because its expansive, porous structure absorbs sound waves and reduces reverberation. By expanding to fill every gap and crack in walls and ceilings, it creates an airtight seal that blocks airborne noise—such as traffic, voices, or plumbing sounds—from leaking through the building envelope. This seamless barrier significantly dampens sound transmission between rooms and from the outdoors, resulting in a much quieter and more private living environment compared to traditional insulation materials.
