InspectAPedia.com InspectAPedia®
 

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia

  • HOME
  • AIR CONDITIONING
  • ELECTRICAL
  • EXTERIORS
  • HEATING
  • HOME INSPECTION
  • INTERIORS
  • PLUMBING
  • ROOFING
  • SEPTIC SYSTEMS
  • STRUCTURE
  • WATER SUPPLY
  • ENERGY SAVINGS
  • ENVIRONMENT
  • INDOOR AIR IAQ
  • INSULATION
  • MOLD INSPECT TEST REMOVE
  • NOISE
  • ODORS
  • SOLAR ENERGY
  • VENTILATION
  • EXPERTS DIRECTORY
  • CONTACT US


Mobile Phone/PDA website viewMobile View
INTERIORS of buildings

ACOUSTICAL SEALANT CHOICES
AIR BYPASS LEAKS
AIR LEAK DETECTION TOOLS
AIR SEALING STRATEGIES
ANIMAL ENTRY POINTS in buildings

ANTI SCALD VALVES
APPLIANCE EFFICIENCY RATINGS

BATH & KITCHEN DESIGN GUIDE

BATHROOM VENTILATION
BASEMENT HEAT LOSS
BLOWER DOORS & AIR INFILTRATION
BLOWER FAN CONTINUOUS OPERATION
BLOWER FAN OPERATION & TESTING
CHIMNEY INSPECTION DIAGNOSIS & REPAIR
COMBUSTION AIR for TIGHT buildings
CRAWL SPACES
ENGINEERED WOOD Products

FLOOR TYPES & DEFECTS

HOUSEWRAP AIR & VAPOR BARRIERS
HOUSE DOCTOR, how-to be

ICE DAM PREVENTION
INSULATION IDENTIFICATION GUIDE
INSULATION INSPECTION & IMPROVEMENT
INSULATION LOCATION - WHERE TO PUT IT
INSULATION MOLD
INSULATION R-Values & Properties
LOG HOME WALL INSULATION VALUES

MOLD INFORMATION CENTER

NOISE / SOUND DIAGNOSIS & CURE
  Air Leak Noises
  AIR CONDITIONING & HEAT PUMP NOISES
  Animal Noises
  Appliance Noises
  Chimney noises
  Door Options for Sound Reduction
  Duct Insulation for Soundproofing
  DUCT VIBRATION DAMPENERS
  Dripping Water Sounds
  Electric Motor Noises
  Electrical System Noises
  Fan Noise Control
  Flanking Pathways for Sound
  Floor Noises
  FLOOR NOISE CONTROL
  GAS BURNER Flame & Noise Defects
  Hearing Disabilities & Building Noises
  HEALTH RELATED NOISE COMPLAINTS
  HEATING SYSTEM NOISES
  HISSING NOISES
  Insect Noises in buildings
  OIL BURNER NOISE SMOKE ODORS
  PLUMBING DRAIN NOISE DIAGNOSIS
  PLUMBING DRAIN NOISE REPAIR
  PLUMBING NOISE CHECKLIST
  PLUMBING NOISE CONTROL
  ROOF NOISE TRANSMISSION
  SIDING NOISES
  Sound Control Measures
  Stair & Step Noises
  Structure Noise Transmission
  Temperature-Change Noises
  Wall Noise Transmission
  WATER HEATER NOISES
  Wind Noises
  Window & Door Noises
NOISE CONTROL for FLOORS
NOISE CONTROL for HEATING SYSTEMS
NOISE CONTROL for PLUMBING
NOISE CONTROL for ROOFS
NOISE CONTROL for WALLS
NOISE, PLUMBING CHECKLIST
NOISE, PLUMBING DRAIN DIAGNOSIS
NOISE, PLUMBING DRAIN REPAIR
NOISES, WATER HEATER
NOISES, WATER PUMP

ODORS & SMELLS DIAGNOSIS & CURE

PLASTER TYPE IDENTIFICATION

SOUND CONTROL in buildings
  ACOUSTICAL SEALANT CHOICES
  Principles of Sound Transmission
  How Sound Levels are Measured
  Sound Absorption vs. Sound Isolation
  Sound Isolation Strategies
  Cut Off Flanking Sound Paths
  Door Options for Sound Reduction
  Duct Insulation for Soundproofing
  DUCT VIBRATION DAMPENERS
  Sound Transmission Class Ratings
  Sound Control for Walls
  Sound Control for Floors
  Sound Control for Plumbing
  Properties of Soundproofing Materials
    Acoustical Sealant for Sound Control
    Resilient Channel for Sound Reduction
    Insulation Details for Sound Reduction
    Gasketing for Noise Control
  White Noise & Sound Conditioners
SIDING, Sheathing Identification - Photo Guide

STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
STAIRS, RAILINGS, LANDINGS, RAMPS

THERMAL TRACKING & HEAT LOSS
TRUSS UPLIFT, ROOF
TRUSSES, Floor & Roof

VENTILATION in buildings

WALL FINISHES INTERIOR

WINTERIZE A BUILDING
WOOD Burning Heaters Fireplaces Stoves

More Information

Photograph of  . Guide to Sound Control in buildings: Sound Transmission
InspectAPedia®  -    

  • Principles of sound transmission in buildings
  • How to make a building quiet: sound isolation strategies
  • Sound insulation designs for building walls
  • Sound control for building floors
  • How to control plumbing noises & sounds
  • List of soundproofing materials
  • Tables of sound control data for buildings

Building Noise & Sound Control: This article series presents methods and materials used to control sound transmission in buildings: how to make a quiet home, office, or place of business using sound isolation for ceilings, floors, walls, plumbing, etc.

InspectAPedia offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false-advertising, or junk science. our contact info is at InspectAPedia.com/Contact.htm.

This article series discusses noise and sound control in buildings, and includes excerpts or adaptations from Best Practices Guide to Residential Construction, by Steven Bliss, courtesy of Wiley & Sons. The page top illustration from the above text shows an example of a design to reduce transmission between building floors.

© Copyright 2012 InspectAPedia.com, Daniel Friedman, Steve Bliss, Wiley & Sons, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

Quiet Please! Best Practices Guide to Sound Control in buildings

Our building sound control articles begin here at SOUND CONTROL in buildings. Other noise and sound diagnosis and control articles are found at NOISE / SOUND DIAGNOSIS & CURE where we describe how to locate the source of, identify and correct various building sounds and noises indoors or on occasion, noises from outside that penetrate indoors at annoying levels.

Platform framing of wood walls floors (C) Daniel FriedmanAccording to Best Practices Guide to Residential Construction:

Because of its stiffness, wood framing (photo at left) readily transmits low-frequency sounds and impact noises through wood- frame houses.

This is particularly a problem in floors and walls separating two housing units, but it can also be an issue within a single-family home.

For example, a person with a home office or music room might want to isolate it acoustically from the surrounding rooms so meetings or music proceed in private and so outside noises will not intrude.

Bedrooms located under living spaces can also require special treatment to reduce impact noises from above.

Another kind of noise control is important where a house sits by a highway or under a flight path.

The goal here is to keep outdoor noises from entering the house by reducing sound transmission through windows, doors, and exterior walls and ceilings. Special acoustical windows rated for low sound transmission are often required for substantial reductions in outside noise.

Principles of Sound Transmission

Sound can travel through both air (airborne sound) and solid materials (structure-borne sound). Structure-borne sound can be directly imparted to the building structure by a vibration, such as a humming compressor, or by direct impact, such as a boot stepping on a hardwood floor.

As sound energy travels through a building, it changes from one type of transmission to the other and back, losing energy in each transition. Because of its rigidity, wood framing is a very good transmitter of low-frequency sound and hollow wall cavities and thin doors do little to reduce sound transmission.

How Sound Levels are Measured in buildings - What is a Decibel

Table of typical sound levels in decibels dB (C) J Wiley & Sons Best Practices Steven BlissSound levels are measured in decibels (dB), which are on a logarithmic scale. A sound increase of just 10 dB indicates an increase of ten times the intensity, although our subjective experience is that the sound is twice as loud.

Decibel levels for common sounds are shown in Table 5-14 at left.

Continuous exposure to sounds above about 85 dB can cause hearing loss in most people.

Sound Absorption vs. Sound Isolation in buildings

Sounds in an acoustically “live” room with all hard surfaces will seem loud and harsh due to the sound reverberating off the hard surfaces.

Adding sound-absorptive materials, such as carpeting and soft furniture, will make sound softer and more pleasant within the room, but will do little to reduce the transmission of sound to adjacent rooms.

To reduce transmission requires sound isolation strategies, typically using high- mass materials, double-framed walls, or resilient connections between the drywall and framing.

Sound Isolation Strategies for Indoor Noise Reduction

To keep airborne sound from passing through walls and floors, there are four main strategies:

  • Add Mass: Increase the mass of the wall or floor by using heavy, dense materials.
  • Decoupling: Break the path of vibration with a break in the framing or a resilient connection to the drywall. see Flanking Pathways for Sound and Resilient Channel for Sound Reduction
  • Absorption: Provide sound-absorptive material, such as fiberglass batts, in the cavity. see Insulation Details for Sound Reduction for an example.
  • Sealing: Block airborne sound from leaking through gaps and cracks. see Acoustical Sealant for Sound Control and Gasketing for Noise Control for examples.

A cavity with fiberglass is far more effective at blocking sound if the two wall surfaces (or ceiling and floor surfaces) are mechanically decoupled as in a double-stud or staggered-stud wall. Resilient channel works essentially the same way by breaking the vibration path from the stud or ceiling joist to the drywall.

The hardest sounds to block are low frequency, such as the thumping of a stereo bass. Using decoupled construction, such as double walls or resilient channels, is effective.

Where that is impractical, adding mass can also be effective. Very massive, non rigid materials such as lead or sand are ideal, but doubling or tripling the drywall is also helpful.

-- Adapted with permission from Best Practices Guide to Residential Construction.

Additional suggestions for improving the noise transmission resistance of buildings is found in article links at page left under SOUND CONTROL in buildings. Be sure to also review Roof & Structure Noise Transmission.

Continue reading about methods for sound control in buildings by using the links provided just below.

Questions & Answers regarding this article

.

Ask a Question or Search InspectAPedia

HTML Comment Box is loading comments...

Share this Article      

...

Technical Reviewers & References

Google
  • InspectAPedia.com® - Daniel Friedman - Publisher & Editor.
  • Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education. Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com.
  • InspectAPedia Bookstore lists recommended books, organized by topic & available for purchase. Most of our articles also include a list of recommended books for the specific article topic as well as other references, and information sources.
  • Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
  • Additional technical contributors & reference sources for this article are listed below.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

NOISE / SOUND DIAGNOSIS & CURE
SOUND CONTROL in buildings

  • Marpac, produces white sound generators, a product that they identify as the Marpac sound conditioner. Marpac can be contacted at http://www.marpac.com/ or contact the Marpac Corporation, P.O. Box 560 Rocky Point, NC 28457 Phone: 800-999-6962 (USA and Canada) Fax: 910-602-1435 1-910-602-1421 (worldwide), 800-999- or email: info@marpac.com
  • Sound Oasis sound conditioners are produced by Sound Oasis: http://www.sound-oasis.com/ email: info@sound-oasis.com or 1-866-625-3218
  • Barrier Ultra-R super high-R building panels, produced by Glacier Bay, use Aerogel and are rated up to R-30 per inch, or in Barrier Ultra-r™ panels, R-50 per inch. The company also produces acoustic panels that are Ultra-db resistant and lightweight. Unlike the appliance insulation panels discussed in the original Q&A above on miracle insulation, these Areogel based panels will continue to retain some, though reduced insulating value if punctured, performing at perhaps R-9 per inch. The product is used in marine refrigerators, but in the future may be available as a residential construction product. The company is researching specialized products in medical, transportation, and aerospace applications. Contact: Glacier Bay, Inc., 2930 Faber Street, Union City, CA 94587 U.S.A, (510) 437-9100, Sales and Technical Information - sales@glacierbay.com

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

  • Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
  • Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
  • Decks and Porches, the JLC Guide to, Best Practices for Outdoor Spaces, Steve Bliss (Editor), The Journal of Light Construction, Williston VT, 2010 ISBN 10: 1-928580-42-4, ISBN 13: 978-1-928580-42-3, available from Amazon.com
  • ...

Duct Insulation for Soundproofing

Fiberglass duct insulation (C) Daniel FriedmanAs stated in Best Practices Guide to Residential Construction: Use fiberglass ductboard or fiberglass duct liners to quiet the noises of fans and moving air. Avoid sharing a common duct between two rooms that need sound privacy.

Elaborating on some duct insulaton considerations: HVAC experts advise us that conventional practice is to insulate the interior of metal ductwork in order to minimize transmission of HVAC equipment sounds throughout a building. Some fiberglass duct liners are plastic coated and may be able to be cleaned using gentle procedures. But most common is the use of un-faced fiberglass duct interior insulation, typically treated with a surface resin binder to help reduce movement of fiberglass particles into the air stream.

Our fiberglass lined duct insulation photo (left) shows clean new metal ductwork with a pink fiberglass mat sound and temperature insulation installed on the duct interior.

However our work on indoor environmental and air quality topics suggests that from an indoor air quality maintenance view, we perfer to see insulation on the exterior of metal ducts. That approach permits the ducts to be cleaned, and it reduces the chances of mold growth in the ductwork. See DUCT SYSTEMS and see Other Places to Look for Hidden Mold for more about places to look for duct system defects and hidden mold on HVAC systems. Mold in Fiberglass Insulation illustrates problem mold growth in fiberglass inculation including in duct systems.

Construction of HVAC ducts from foil-faced insulating board combines sound and temperature insulation with aluminum foil to product ductwork that is quiet and cleanable.

Use of White Noise to Mask Sounds in buildings

Sleep Mate white noise generator (C) Daniel FriedmanAs we show in our photo (left), white noise generators may also be used in locations where an extra measure of privacy is required. This installation is in the waiting room outside offices used by psychotherapists.

White noise is a sound containing a blend of all the audible frequencies distributed equally over the range of the frequency band. When this sound is generated it tends to make unintelligible or even less noticeable other sounds such as nearby conversation.

The proper setting for a white noise generator is not to make the output as loud as possible. Rather, set the volume on the white noise machine to just mask the noise (or conversation) to be overcome. Setting the white noise volume higher than that level risks making the white noise itself an annoyance in the building.

Shown is the Sleep Mate™ sound generator produced by Marpac. In addition to white noise, sound conditioners may produce sounds of nature such as that of a river or brook, lakeshore, surf, thunderstorms, or rainfall. Sound Screen® and SleepMate® are registered trademarks owned by Marpac Corporation.

 

Home About Us Accuracy Contact Us Content Use Policy Privacy Website Description © 2012 Copyright InspectAPedia.com