Overview
EN ISO 12354-3:2017 - "Building acoustics - Estimation of acoustic performance of buildings from the performance of elements - Part 3: Airborne sound insulation against outdoor sound" (CEN adoption of ISO 12354-3:2017) defines a calculation model to estimate the airborne sound insulation of façades and other external building surfaces. The standard bases predictions on the sound reduction index of façade elements, accounting for both direct and flanking transmission, and produces results that correspond approximately to field measurements carried out in accordance with ISO 16283‑3. Calculations can be performed in frequency bands or as single-number ratings, and outputs can feed into indoor sound level estimates (see Annex E).
Key topics and technical requirements
- Calculation model: Principles and procedures to combine element sound reduction data into a façade-level prediction, including treatment of small technical elements and composite parts (Annex B, D).
- Direct and flanking transmission: Explicit inclusion of flanking paths in the model to reflect realistic façade performance.
- Frequency and single-number results: Support for one‑third-octave/octave band calculations and derivation of single-number indices (e.g., as per ISO 717‑1).
- Input data: Use of laboratory/measured sound reduction indices of constituent elements (per ISO 10140 series and ISO 12354-1 guidance).
- Accuracy and limitations: Guidance on expected accuracy, restrictions of applicability (model primarily developed from dwelling-type constructions), and recommendations for applying safety margins or verifying with field measurements.
- Informative annexes: Practical guidance (Annex F), indoor level estimation methods (Annex E), examples (Annex G), and symbol lists (Annex A).
Practical applications
- Predicting façade airborne sound insulation during design, enabling early noise-control decisions without waiting for on-site measurements.
- Estimating indoor sound pressure levels from outdoor sources (e.g., road traffic), useful for space planning, ventilation/opening design, and glazing selection.
- Supporting compliance assessments, specification writing, and performance-based design in building projects.
- Feeding acoustic performance inputs into building simulation tools and product development for windows, façades and cladding systems.
Who should use this standard
- Acoustical consultants and engineers
- Façade and building envelope designers
- Building physicists and researchers
- Manufacturers of windows, façade systems and acoustic components
- Local authorities and building code assessors
- Software developers creating acoustics prediction tools
Related standards
- ISO 16283‑3 (field measurements for façades)
- ISO 717‑1 (rating of sound insulation)
- ISO 10140‑1 (laboratory measurement of building elements)
- ISO 12354 series (other parts on room-to-room and impact sound)
EN ISO 12354-3:2017 is a practical, standardized method for estimating outdoor-to-indoor airborne sound performance, enabling informed decisions in façade design, acoustic specification and regulatory compliance.
