Presented By: Jim O Neill Acoustics
Topics STC and IIC 101 Sound in floors Sound in walls
Noise In Multifamily
Measurements of Noise Two ASTM Standards STC Sound Transmission Classification Measurement of Airborne noise Talking, music, television Single number result over a frequency range from 125 to 4000 Hz 50 in a laboratory setting is considered passing by Standard Setting Organizations IIC Impact Insulation Classification Measurement of Vibration Noise Footfall, washing machine Single number result over a frequency range from 100 to 3150 HZ 50 in a lab setting is considered passing Standard for Multi-family
General Ways of Improving Noise Airborne Noise - STC Example: talking, music, television Controlled by adding mass to the assembly so the heavier the flooring assembly, the better job of controlling airborne noise Walls are different more money to add mass Small holes in system create big noise openings Vibration Noise IIC Example: footfall, washing machine Controlled by isolation and structure, void, spring structure between two solid objects Connections are problematic and flanking vibration from floors to walls to lower levels
Understanding the ASTM E492 Impact Noise 70 60 50 40 30 20 10 0 1 3 5 7 9 11 13 15 QQ Bare Gypsum Enka Bare Gypsum Curves are matched to standards for a given IIC number. Results are limited by any given frequency exceeding 8 points of the standard curve. Results are limited by overall deficiencies exceeding the standard (above the curve).
Noise Anatomy Product Effectiveness Top Side works from 1000 Hz and Up, rather eliminating the high frequencies of the curve. The gypsum concrete and Entangled Net work from 400 Hz and Up and provide the means to achieve code across the board, increase FF, better mid-range performance; increase the thickness of the Entangled Net and improve at the higher frequencies. Bottom side resilient channels work in the lower frequency range, 1000 Hz and below. It is the quality of the installation that typically causes poor performance in the field.
Ceiling Details & Flanking Flanking is the non-direct route that noise can take to short circuit a sound system Occurs on the floor side if all penetrations and wall perimeters are not isolated Five paths on the ceiling side A. Resilient channel fasteners direct connect gypsum ceiling to the joist or ride on the joist B. Resilient channel comes in direct contact with the wall structure C. Gypsum ceiling is in contact with the wall structure D. Gypsum ceiling is in contact with the gypsum wall E. Gypsum wall is in direct contact with the subfloor
Proper Isolation of Ceiling A Short Circuit Resilient Channels B Resilient Channel in contact with wall structure C Gypsum ceiling in contact with wall structure D Gypsum wall in contact with gypsum ceiling E Gypsum wall in contact with subfloor
Questions on floors
Sound Control for Exterior Walls How is sound control managed in exterior walls? Similar to the floor/ceiling assembly with the use of resilient channels, insulation, and an entangled net. Think of a wall as a floor/ceiling assembly turned vertically
Keys for great sound in walls 1. Air barrier 2. Mass 3. Mass Spring Mass Design
Why is sound control in Exterior wall systems important? The World Health Organization estimates that 70 percent of the global population will live in cities and towns by 2050, up from just 50 percent today. People living closer together HUD Building Requirements
HUD-defined noisy locations Urban noise Train/light rail noise Street traffic Air traffic HUD Requires on >45 for all exterior wall in HUD defined Noisy Locations
Standard exterior wall system Drywall 2 by 6 studs Batt insulation Sheathing WRB Fiber Cement siding STC rating 41 Does not meet HUD STC requirement Lacks current Rainscreen technology
What is a Rainscreen System?
Keene High Performance System Drywall Resilient channel 2x6 Studs Batt insulation Sheathing WRB Driwall Rainscreen Fiber Cement siding STC rating 52 Exceeds Code requirements for HUD As well as add moisture control by add current Rainscreen technology
Structural Insulated Panel Association 5/8 gyp, SIPS, 5/8 gyp
Exterior Walls are hard to build Consumers want.. Quiet exterior walls Meet or Exceed HUD Sound Requirements Energy Efficient No Drafts Durable Wall System Water tight Rot free
Questions Floor and wall are different HUD defined Noisy Locations Mass Mass - Spring Mass Air Barrier
What is changing in Exterior Walls Energy Codes Does this effect moisture related issues? Moisture related issue are on the rise in wall systems Mold Rot
For every action, there is an equal and opposite reaction. -Sir Isaac Newton How do you decrease wetting potential? Think Keene Driwall Rainscreen!!! Jim O Neill
Keene High Performance System Meeting HUD sounds requirements Latest rainscreen system Small changes = Big performance