Common methods for controlling acoustic leakage through doors and partitions.

• A. Hollow core doors with loose seals.
• B. Solid core doors with tight seals, door sweeps, perimeter seals around frames, acoustic gasketing, mass-loaded vinyl where appropriate, and decoupled assemblies.
• C. Use only paint to seal gaps.
• D. No method is effective.

Answer: (B)

The key idea is to create a high-mass, continuous, well-sealed barrier around doors to prevent airborne sound from leaking through gaps and through the door itself, and to interrupt how vibrations travel by decoupling the door from the surrounding structure when possible.

Hollow core doors are lightweight and have porous interiors, so they transmit sound easily even if there are some seals. They don’t provide the solid, dense barrier needed for good acoustical performance. Solid core doors, in contrast, offer much greater mass and stiffness, which blocks more sound. When you pair a solid core door with tight seals, door sweeps to close the bottom gap, perimeter seals around the frame, and proper acoustic gasketing along the door edges, you create a continuous enclosure that minimizes leakage paths.

Mass-loaded vinyl can be added where extra mass is beneficial, helping to increase the barrier’s impedance without excessively thick assemblies, particularly in retrofit situations or where space is constrained. Decoupled assemblies further improve performance by interrupting the vibration path between the door and the surrounding wall or frame, reducing how structural noise couples into the doorway area.

Paint on gaps or any cosmetic sealing won’t stop sound, because it doesn’t provide a true airtight seal or added mass. And claiming no method is effective ignores well-established practices for sound isolation around openings.