# Are New Apartments Soundproof? STC and IIC 50 Explained > The 2024 IBC sets STC and IIC 50 as the minimum between units. What the ratings mean and what to test on a tour. URL: https://newapartmentsaustin.com/guides/are-new-apartments-soundproof/ Last-Modified: 2026-10-25 Guide · Lease-Ups # Are New Apartments Soundproof? What STC and IIC 50 Mean The 2024 IBC sets STC and IIC 50 as the minimum between units. What the ratings mean, how building types differ, and what to test on a tour. Written by New Austin Apartment Team [/about/#new-austin-apartment-team →](/about/#new-austin-apartment-team) · Reviewed by the team, Spirit Real Estate Group, LLC · Updated October 25, 2026 · 5 min read - Free to you, and your rent is the same either way - 144 new communities tracked (as of Oct 25, 2026) - Prices pulled every morning ![Quiet new apartment bedroom with oak floors and a large window](/images/featured/quiet-new-apartment-bedroom-with-oak-floors-and-a-.webp) - Licensed Texas brokerage Spirit Real Estate Group, LLC, TREC #562021 - Free to renters Communities pay the brokerage. Your rent is the same either way. - Prices pulled every morning Every card shows the date and time it was pulled - Score can't be bought Commission rates never affect score, sort, placement, or picks ## Are new apartments soundproof? Are new apartments soundproof? No, they are not completely silent, but US builders must meet specific baseline minimums today. The 2024 International Building Code (IBC) legally requires STC 50 and IIC 50 ratings between dwelling units. We see firsthand how noise impacts daily life for our clients. A rating of 50 is just a starting point, and premium buildings often aim higher. Understanding the exact building layout makes all the difference in your comfort. We ask for these critical noise details on lease-up buildings [/lease-up-apartments/ →](/lease-up-apartments/) before you ever take a tour. This proactive step ensures you only visit properties that match your noise tolerance. Let’s break down exactly what these numbers mean and how to spot a quiet space. ![Cross-section diagram of a floor-ceiling assembly labeled STC and IIC](/images/content/cross-section-diagram-of-an-apartment-floor-ceilin.webp) ## What STC and IIC measure These two metrics measure different types of sound transmission through walls and ceilings. STC tracks airborne noise, while IIC tracks physical impacts. Our team uses these ratings to set realistic expectations for clients. An STC rating apartment metric of 50 means the wall blocks roughly 50 decibels of sound. A loud conversation hits about 60 decibels. This means roughly 10 decibels still bleed through an STC 50 wall, which sounds like a faint whisper. | Rating | What it blocks | Applies to | 2024 IBC minimum | Premium Target | | --- | --- | --- | --- | --- | | STC (Sound Transmission Class) | Airborne sound: voices, TV, music | Walls and floor-ceilings between units | 50 | 55-60+ | | IIC (Impact Insulation Class) | Impact sound: footsteps, dropped items | Floor-ceilings between stacked units | 50 | 55-60+ | Higher numbers always provide better isolation for an IIC rating floor and STC walls. Premium US developers often target STC 55 or higher to block heavy bass from home theaters. > **Lab vs. field performance** > > Ratings are often tested on a pristine assembly in a laboratory environment. Real-world results usually drop by up to 5 points. This performance gap happens because of standard construction flaws, unsealed electrical outlets, and tiny gaps under doors. ## Building type matters The structural materials used in construction directly dictate how noise travels through a building. Wood-frame structures transmit more impact noise, while concrete structures block it much better. We frequently tour both garden-style wood layouts and concrete high-rises across the country. Both methods can technically meet the legal 50 minimums. Here is how the main structures handle daily noise: - **Wood-frame:** These buildings use layered assemblies to reach code. Builders often add resilient channels (like the RC-1 standard), Green Glue damping compound, or specialized acoustic drywall. Impact noise from heavy footsteps is still the most common complaint here. - **Concrete:** Heavy concrete slabs naturally block airborne and impact sounds extremely well. Hardwood or tile placed directly on concrete can still send clicking noises downward. Premium buildings solve this by installing rubberized underlayments like Maxxon Acousti-Mat beneath the hard flooring. Ask the leasing office for their specific STC and IIC figures. A blank stare from the staff is a major red flag for noise-sensitive renters. ## What to test on a tour Testing the unit yourself is the best way to verify actual noise levels before signing a lease. You should simulate real-world conditions while walking through the empty space. Our clients use a few simple methods to uncover hidden sound issues. Following a clear process removes the guesswork from property tours. Preparing for your visit guarantees you test the right areas. Here is a checklist for your next walkthrough: 1. **Talk test:** Have someone speak in the adjacent hallway with the front door firmly closed. 2. **App measurement:** Download the free NIOSH Sound Level Meter app on your phone. Check the ambient decibel reading in the bedroom with the HVAC running. 3. **Footstep test:** Schedule your tour during peak evening hours. Listen closely for heavy walking if the unit above is occupied. 4. **Shared-wall check:** Ask for the floor plan of the adjacent unit. You want to know if their kitchen cabinets share a wall with your primary bedroom headboard. 5. **Outside noise:** Stand near windows facing highways, parking garage entrances, or the community pool. Single-pane glass will let a lot of this exterior noise inside. 6. **Mechanical noise:** Locate the elevator shafts, trash chutes, and heavy rooftop AC units. Units sharing a wall with these will hear constant hums and vibrations. Our tour checklist [/guides/new-apartment-move-in-checklist/ →](/guides/new-apartment-move-in-checklist/) includes these specific sound checks alongside the rest of the walk-through steps. Printing this list out ensures you remember every test. Being thorough today prevents major stress next year. ## Unit location tradeoffs Where a unit sits inside the building footprint heavily influences your daily noise exposure. Top-floor corners are generally the quietest, but they often come with higher utility costs. We help clients balance these specific compromises based on their lifestyle priorities. Reviewing the full property map reveals the best hidden gems. Making a smart choice requires weighing the pros and cons. | Location | Quieter for | Watch for | | --- | --- | --- | | Top floor | Eliminates all heavy footsteps from above | Proximity to humming roof AC equipment and higher summer heat | | Corner unit | Fewer shared walls with loud neighbors | More exterior exposure to street traffic or wind noise | | Away from amenities | Less screaming from the pool and courtyard | May require a much longer walk to your reserved parking spot | | Away from elevator and trash | Zero mechanical clanking or hallway chatter | Longer daily walk carrying heavy groceries | | Away from construction phase | Less daytime hammering and truck beeping | Ask management for the specific phase completion dates | Picking a unit tucked at the end of a long corridor usually guarantees the lowest foot traffic. If a later phase is still going up next door, our guide on moving into a building that’s still finishing [/guides/moving-into-building-still-finishing/ →](/guides/moving-into-building-still-finishing/) covers construction noise hours. ## Use it in your comparison Factoring sound isolation into your final decision prevents costly broken leases later. If two buildings look identical on paper, actual soundproofing quality is the ultimate tiebreaker. We always advise clients to prioritize sleep quality over flashy amenities. This practical approach saves major headaches down the road. Comparing facts side-by-side reveals the true value of a property. Our comprehensive guide on comparing buildings [/guides/compare-new-apartment-buildings/ →](/guides/compare-new-apartment-buildings/) shows exactly where noise fits into a smart decision matrix. Finding out are new apartments soundproof enough for your needs requires asking the right questions. Bring your smartphone decibel meter, demand the specific STC numbers, and listen closely during your tour. Start reviewing floor plans today to identify those quiet, tucked-away corner units. Learn more about Lease-Ups Open buildings in lease-up or their first 24 months, sorted by stage and fill estimate, with what's finished confirmed in writing. Open Lease-Ups [/lease-up-apartments/ →](/lease-up-apartments/) Why it goes wrong ## What goes wrong at a building that's still filling Problem 1 ### The amenities aren't open yet A pool, gym, or garage can open months after the first move-ins. The listing often shows the finished rendering, not the date it opens. Problem 2 ### Construction continues next door Phased projects keep building after phase one fills. Noise hours, dust, and parking changes can run through your first lease. Problem 3 ### Small defects show up early New units often need caulk, door, appliance, or HVAC balancing fixes in the first weeks. Without a written punch list, they wait. So we confirm amenity open dates and construction status in writing, and send a punch list at day 7 and day 30. Straight answers ## Questions about this topic Direct answer first, then the source and date. If your question isn't here, ask us on the form or by text. ### What does STC 50 mean? STC (Sound Transmission Class) rates how well a wall or floor blocks airborne sound like voices or TV. 50 is the 2024 IBC minimum between units; higher numbers block more. ### What does IIC 50 mean? IIC (Impact Insulation Class) rates how well a floor-ceiling assembly blocks impact sound like footsteps. 50 is the 2024 IBC minimum between stacked units. ### Is a top-floor unit quieter? No one walks above you, but roof equipment, rain, and heat can add noise. Ask what's on the roof above the unit. ### Can you guarantee a price or approval? No. We confirm both before you sign. Keep reading ## More guides on this topic ![Clipboard checklist on a new quartz kitchen counter with floor-to-ceiling windows](/images/featured/clipboard-checklist-on-a-new-quartz-kitchen-counte.webp) ### New Apartment Tour and Move-In Checklist What to check on a new-build tour and in the first 48 hours: sound ratings, HVAC sized for a 99°F design day, finished amenities, and the move-in condition form. [New Apartment Tour and Move-In Checklist →](/guides/new-apartment-move-in-checklist/) ![Four printed apartment comparison cards on an oak table](/images/featured/four-printed-apartment-comparison-cards-laid-out-o.webp) ### How to Compare New Apartment Buildings Side by Side Compare on true monthly, year two, and 24-month total, not headline rent. Then add stage, what's finished, and fee disclosure. [How to Compare New Apartment Buildings Side by Side →](/guides/compare-new-apartment-buildings/) The 60-second form ## Tell us what you need. We make the calls. You don't have time to call 20 leasing offices. We do, and confirm the unit, the special, and the written fee sheet the same day during hours. 1. 1 Same day We call or text during hours with a shortlist plan. 2. 2 In writing Unit, special, end date, and fee sheet confirmed before you tour. 3. 3 Year two shown Every pick shows year two at 0% and +3%, plus a 24-month total. Prefer to talk? Call or text 512-000-000 [tel:+1512000000 →](tel:+1512000000) , Mon-Fri 8 AM-8 PM · Sat 9 AM-6 PM · Sun 12-5 PM. Free, same day during hours ## Get my shortlist Step 1 of 3 ### Thanks, we have your details. We'll call or text the same day during hours with your shortlist plan. Related pages ## Related board views Board view ### Lease-Ups Buildings already open and filling, sorted by stage and fill estimate, with what's finished and what the special does to your monthly cost. Open Lease-Ups→ [/lease-up-apartments/ →](/lease-up-apartments/) Board view ### New Build Board Every in-scope community on one map, with base rent, the special, net effective, true monthly, and year two pulled every morning. Open New Build Board→ [/new-construction-apartments/ →](/new-construction-apartments/) Board view ### Specials Specials confirmed within the last 7 days, each decoded to net effective and year two, with base rent shown beside every discount. Open Specials→ [/apartment-specials/ →](/apartment-specials/) ![](/images/misc/dusk-view-of-new-limestone-and-glass-apartment-tow.webp) Free to you, and your rent is the same either way ## You don't have time to call 20 leasing offices. We do. Send us your move date and all-in budget. We confirm the unit, the special, and the written fee sheet the same day during hours, then show you year two before you tour. Get my shortlist → [/contact/ →](/contact/) See the New Build Board [/new-construction-apartments/ →](/new-construction-apartments/) Call or text 512-000-000 [tel:+1512000000 →](tel:+1512000000) We don't guarantee pricing or approval. The community sets both, and we confirm them before you sign.