If the goal is quiet rather than warmth, the foam choice flips: open-cell is the sound tool. Its soft, open structure absorbs airborne noise far better than dense closed-cell, which is why it shows up in media rooms, bedrooms, home offices and shared walls.
What open-cell does for sound
Open-cell fills a wall or ceiling cavity completely and dampens the airborne sound - voices, TV, music - that travels through gaps and cavities. It will not turn a wall into a recording studio on its own, but it meaningfully reduces the transfer that batt leaves open.
Honest expectations
Spray foam handles airborne noise; true soundproofing against impact noise also needs mass and decoupling (resilient channel, extra drywall). A good installer will tell you where foam is the right eighty-percent solution and where you need more.
Works for demising walls, basements-turned-studios and quiet home offices. Get a free quote. See open-cell.