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Insulation of Building Against Highway Noise

Table of Contents

  1. Chapter 1 INTRODUCTION
    1. 1.1 Purpose
    2. 1.2 Basic Concepts of Noise Insulation
    3. 1.3 Use of This Manual
    1. 2.1 Introduction
    2. 2.2 EWNR Values for Walls
    3. 2.3 EWNR Values for Roof-Ceiling Constructions
    4. 2.4 EWNR Values for Windows and Doors
    5. 2.5 EWNR Values for Through-The-Wall Air Conditioners
    6. 2.6 Composite EWNR Values for Two or More Elements
    7. 2.7 Interior Absorption Adjustment
    8. 2.8 Noise Reduction Procedure
    9. 2.9 Modifications to Increase Noise Reduction
    1. 3.1 Introduction
    2. 3.2 Equivalent Noise Level
    3. 3.3 Noise Measurement Equipment
    4. 3.4 Noise Level Measurement Procedure
      1. 3.4.1 Exterior Measurements
      2. 3.4.2 Interior Measurements
      3. 3.4.3 Leq Computation Procedure
      4. 3.4.4 Use of an Artificial Noise Source
    1. 4.1 Introduction
    2. 4.2 Ventilation Requirements
    3. 4.3 Ventilation System Noise Levels
    4. 4.4 Energy Considerations
    1. 5.1 Introduction
    2. 5.2 Present Value Calculations
    3. 5.3 Operating Costs
    4. 5.4 Sources of Cost Data
    5. 5.5 Worksheet for Cost Analysis
  7. APPENDIX A Development and Evaluation of EWNR Rating Scheme
  8. APPENDIX B Use of the Manual
  9. APPENDIX C Calculation of Internal Absorption Adjustment Factors


  1. Exterior Wall Noise Rating (EWNR) Values in dB For Standard Exterior Constructions
  2. Adjustments to Basic EWNR Values Due to Modifications
  3. EWNR Values in dB for Basic Roof-Ceiling Constructions
  4. Adjustment to Basic EWNR for Addition of Absorption in Nonvented Ceiling/Joist Spaces
  5. Effects of Venting Attic Space Constructions On EWNR Values With and Without Absorption
  6. Adjustment to Basic EWNR to Account for Building Self-Shielding
  7. EWNR Values for Common Window Assemblies
  8. EWNR Values for Commonly- Used Doors
  9. EWNR Values for Through-the-Wall Air Conditioners for Vents Open and Closed
  10. Adjustment Factors for Interior Room Absorption
  11. Relative Aspects of Noise Reduction Modifications to External Walls
  12. Table for Combining Noise Levels in Decibels
  13. Yearly Degree-Days For Various Cities Based on 65°F, (18°C)
  14. Infiltration Constant, C, for Typical Residential Buildings
  15. Coefficients of Thermal Transmittance (U-Factors) for Common Constructions in Btu/hr ft² °F
  16. Adjusted U-Factors in Btu/hr ft² °F for Walls With Stud-Space Absorption
  17. Values of Thermal Transmittance (U-Factor) in Btu/hr ft² °F for Commonly-Used Windows
  18. Values of Thermal Transmittance (U-Factor) in Btu/hr ft² °F for Commonly-Used Solid Core Exterior Doors
  19. Characteristics of Heating Fuels
  20. Factors for Calculating Present Value (PV) of Replacement Costs (RC) Based on a 10% Discount Rate
  21. Cost Services
  22. Correlation Coefficients and 90 Percent Confidence Intervals for Prediction of Interior A-Weighted Noise Levels for 11 Single Number Transmission Loss Rating Schemes
  23. Ninety Percent Confidence Intervals for Comparison of Single Number Calculations With Third Octave Band Calculations
  24. Values of 10 log S/A in dB for Residential Building Rooms With One and Two Walls Exposed


  1. Conceptual Illustration of Noise Being Transmitted Through a Structure
  2. Conceptual Illustration of How Heavy Structures Transmit Less Noise Than Lightweight Structures
  3. Conceptual Illustration of the Two Mechanisms Comprising Total Noise Reduction
  4. Organization of the Manual by Chapters
  5. Elements of the Overall Manual Procedure Covered in Chapter 2
  6. Illustration of Two Commonly-Used Roof-Ceiling Constructions
  7. Graph for Determining Composite EWNR for Two Wall Elements for Several Ratios of the Area of One Component to the Total Area of Both Components
  8. Conceptual Illustration of the Three Major Types of Paths by Which Noise is Transmitted to Building Interiors
  9. Elements of the Overall Manual Procedure Covered in Chapter 3
  10. Field Measurement Data Log
  11. Location of Sound Level Meter and Microphone for Exterior Noise Level Measurements
  12. Field Measurement Data Sheet
  13. Worksheet for Manual Leq Calculation
  14. Illustration of Correct Placement of Artificial Noise Source
  15. Measurement Locations for an Artificial Noise Source
  16. Worksheet for Cost-Estimating Noise Reduction Alternatives
  17. Worksheet No. 1 - Calculation of Building Noise Reduction
  18. Worksheet No. 2 - Composite EWNR Calculation for Two Elements
  19. Worksheet No. 3 - Fuel Savings Due to Acoustical Modifications
  20. Worksheet No. 4 - Leq Calculation
  21. Conceptual Illustration of Noise Reduction Effect of a Building
  22. Typical Highway Noise Spectra
  23. Standard Highway Noise Spectrum
  24. Exterior Wall Noise Rating Curve Designed to Relate to Interior A-Weighted-Noise Levels for Highway Noise Levels
  25. Flow Diagram for the Design of Noise Insulation of Buildings
  26. Values of 10 log S/A for Living Rooms, Kitchens and Bedrooms in Residential Buildings with One Wall Exposed to Noise Source
Updated: 7/6/2011
HEP Home Planning Environment Real Estate
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000