Atrium Carceri is typically described as dark ambient, black ambient and ambient industrial music. Similar to projects like Lull and Lustmord, Atrium Carceri uses synthesizers, sound effects, samples from films and anime, piano and other instrumentation to create "slow rhythms, bitter melodies and complex textures" generally based on themes of desolation, loneliness (especially solitary confinement) and environmental decay. Atrium Carceri has been praised by music critics and embraced by a cult audience for its depth of atmosphere. As described by one reviewer, "Heath creates a world where time collapses, where the ancient world of conjured spirits, the physical limitations of being all too human, and the infinite outreach of potential futuretech, all coexist." The project name, "Atrium Carceri", means "prison hall" in Latin - however, "carceri" is in the wrong declension class. The proper name would have been "Atrium Carceris".