Structure-Borne Sound

Structure-borne sound is vibration energy propagating through solid building elements (walls, floors, columns, beams) that radiates as airborne sound into occupied spaces. Unlike airborne sound, which loses energy at each boundary, structure-borne sound can travel long distances through a building with relatively little attenuation, making it a persistent source of complaints in multi-storey buildings. Sources include footsteps, machinery, lifts, pipes, and building services equipment. Structure-borne sound transmission is governed by the vibration levels at the source, the coupling efficiency between the source and structure, the structural transmission path losses, and the radiation efficiency of the receiving room surfaces. Mitigation requires vibration isolation at the source (resilient mounts, inertia bases), structural breaks in the transmission path (isolation joints, resilient connections), and decoupled surface treatments (floating floors, independent wall linings). ISO 10848 provides measurement methods for structure-borne flanking transmission at junctions.