Field impact insulation class (FIIC)—A case study

Abstract

Impact noise in buildings constitutes a potentially serious problem because of the short duration, high intensity sounds involved [U.S. Department of Housing and Urban Development, Airborne, Impact, and Structure Borne Noise, Chapter 7 (1967)]. Since 1974, the State of California has tried to manage this problem by instituting the California Noise Insulation Standards, which require any multi-family dwelling to provide an impact insulation class (IIC) rating of 50 based on laboratory tests, or a field impact insulation class (FIIC) rating of 45 based on field tests [Office of Noise Control, California Noise Insulation Standards, 1–7 (1988)]. Concern about the acceptability of floor ceiling assemblies is increasing due to increased awareness of the problem and larger numbers of people moving into apartments, condominiums and townhomes throughout California. Western Electro-Acoustic Laboratory (WEAL) had the opportunity to witness the installation of floor ceiling assemblies in an apartment complex in Bakersfield, California. Six different assemblies were tested to determine how the FIIC value changed when minor modifications were made to the standard floor ceiling assembly. WEAL will show the results of the field-tested assemblies and compare the data with typical laboratory results for similar constructions.