The sound performance of a floor/ceiling assembly in a building is the result of 5 key components of the structure. These construction components will dictate the underlayment product and associated materials specified.
(1) – This could be concrete slab at various thicknesses (for example, 6 inches or 8 inches thick), wood joist and wood truss systems, or a combination structure of concrete, metal & wood.
(2) – Ranges from hard surface flooring like ceramic tile, stone, marble and natural wood, to soft surface flooring like carpet and luxury vinyl tile.
(3) – Concrete Slab construction could have no ceiling included, a ceiling system attached directly to the bottom of the slab, or a suspended ceiling. Suspended ceilings are generally either gypsum board with plaster or “architectural” ceiling board held in place with a metal grid system. Wood joist and truss systems would include a ceiling unless it is “open” beam construction.
(4) – Is the space created by the ceiling attached to the sub-floor structure. The depth of the air plenum and its use, such as to include insulation material, recessed lighting, electrical wiring, HVAC duct work, etc. determines its value in reducing sound.
(5) – This is a critical construction component often overlooked. Perimeter Isolation Barrier (PIB) material and sound absorbing caulking should be used to prevent sound “flanking” around the floor assembly. Also, adhesives are better than using nails or screws which will transmit sound through the floor assembly
So as the architect, contractor, owner/user of the room, each step in the process of creating the specific condominium, office, home impacts the sound reducing and insulating performance of the total floor assembly. How is the building designed? How did the contractor build/install the components? What finished flooring was selected by the designer/decorator/end user?