# 056 - Building Acoustics: How Sound Actually Works in Buildings Page: https://stenobird.com/podcast/architect-exam-podcast-7271936/056-building-acoustics-how-sound-actually-works-in-buildings Text version: https://stenobird.com/podcast/architect-exam-podcast-7271936/056-building-acoustics-how-sound-actually-works-in-buildings.md Podcast: [Architect Exam Podcast](https://stenobird.com/podcast/architect-exam-podcast-7271936) Published: 2026-03-02T10:30:00+00:00 Episode link: https://academy2.youngarchitect.com/building-acoustics/ Audio file: https://traffic.libsyn.com/secure/bab13b25-964b-4ced-be11-af2e0ce800df/056_-_Acoustics.mp3?dest-id=4956905 Processing state: not_requested JSON: https://stenobird.com/v1/public/podcasts/architect-exam-podcast-7271936/episodes/056-building-acoustics-how-sound-actually-works-in-buildings Duration seconds: 1915 ## Resource Building acoustics explained: STC, IIC, and NRC are the three rating systems every architect needs to know. This episode breaks down how sound actually works in buildings and what each rating measures. STC rates how well walls and floors block airborne sound. IIC rates how well floor assemblies block impact sounds. NRC measures how much sound a material absorbs within a room. We explain why a material can be great at absorbing sound but terrible at blocking it. You'll also learn why the IBC requires both STC 50 and IIC 50 between dwelling units, how to upgrade a basic wall assembly step by step, and the flanking paths and spec mistakes that compromise acoustic performance. 📝 Key topics covered: STC ratings: blocking airborne sound through walls IIC ratings: blocking impact sound through floors NRC ratings: absorbing sound within a room IBC Section 1207 requirements for dwelling units Wall assembly upgrades: mass, insulation, decoupling, and sealing Flanking paths and common acoustic spec mistakes ⏱️ Chapters: (0:00) Introduction (1:28) Free Study Guide (2:34) Why Sound Matters in Buildings (4:17) Decibels: Measuring Loudness (6:58) Hertz: Measuring Pitch (8:17) STC: Sound Transmission Class (16:07) IIC: Impact Insulation Class (20:34) NRC: Noise Reduction Coefficient (24:09) Bringing It All Together (26:31) Practical Tips and Scenarios (29:33) Acoustics Recap 📖 Read the full blog post 📝 Download the FREE 2-page Building Acoustics study guide 🎯 Get access to all ARE study materials with the ARE 101 Membership 🎯 Join our 10-week ARE Boot Camp 📚 Individual ARE Exam Courses: PPD 101 (Project Planning and Design) PDD 101 (Construction Documents and Specs) Building Codes 101 Mechanical Systems 101 CE 101 (Construction and Evaluation) PcM 101 (Practice Management) PjM 101 (Pr… ## Actions - request_transcript: `POST https://stenobird.com/v1/public/podcasts/architect-exam-podcast-7271936/episodes/056-building-acoustics-how-sound-actually-works-in-buildings/transcription-requests` — Idempotently request low-priority transcript generation for this episode. - read_markdown: `GET https://stenobird.com/podcast/architect-exam-podcast-7271936/056-building-acoustics-how-sound-actually-works-in-buildings.md` — Read the agent-friendly Markdown representation of this episode resource. A page view does not enqueue transcription. Agents should invoke `request_transcript` explicitly when they need this episode processed. ## Transcript Full transcripts are not published on public pages unless there is a clear rights basis.