How to Specify: Acoustic Insulation

This article is part of a series designed to help architects use Source, Architizer’s premier marketplace for building products. For more information on the platform, click here.

If you’re an architect, contractor or do-it-yourselfer, you probably already know how difficult and time-consuming it can be to research and select the building products that are right for your next project. Luckily, Architizer is here to help: Using our product catalog and Source, the new marketplace for building products, we’ve written a collection of “spec guides” on everything from marble to surface-mounted lighting. These will help you understand what factors to consider before making your next specification or purchase and help you to make the perfect product search on Source. Think of them as the ultimate specifier cheat sheet.

With so many incredible concert halls and theaters recently being completed, from MAD’s Harbin Opera House to Herzog & de Meuron’s Elbphilharmonie, now seems like the perfect time to look at the art of specifying acoustic insulation.

Acoustic Insulation

Categorization

Architizer: Building Products > Insulation & Waterproofing > Acoustic Insulation
MasterFormat: 098100

Introduction + Tips

Acoustic insulation is installed in both walls and ceilings, and around pipes, cracks and ducts. Try not to confuse it with acoustic accessories like ceiling or wall panels, which can similarly affect a room’s acoustics but which technically aren’t building materials. No single acoustical solution should be applied to all designs, as each space offers unique parameters that the architect and designer must consider when developing floor plans, selecting materials and designing assemblies.

When you’re specifying acoustic insulation through Source, be sure to provide the proper information on the building’s plan and structural systems, like the walls and ceilings. Also, describe what you need the insulation to do — either in technical terms (STC rating/NRC value) or in your normal human words! This will help the manufacturer know which materials are right for your project.

Different acoustic insulation may be required depending on the type of space or structure it is being specified for. For new-build projects, this could include: wood construction / loft spaces (1), concrete hollow-core slabs (2), plain concrete slabs (3), basements (4) and ceilings and walls (5); diagram via Imbema SMT

Application

• Building Type: Acoustic insulation can be installed in a variety of buildings:
  • Retail and Public Spaces
  • Residential Spaces
  • Offices
  • Bathrooms
  • Gyms
  • Theaters
• Location: Is the building in a loud or quiet area? Where is the insulation going to be installed?
• New Construction or Retrofit: State whether your project is a new building or if it’s being retrofitted. If it’s a retrofit, to what extent are the structural systems going to be renovated? Acoustic insulation is applied to walls and ceilings, and installation can be invasive.
• Layout and plan: Describe the dimensions of the building and upload floor plans, if possible.
• Structural Systems: The type of insulation system used is dependent upon the structural characteristics of your building, so provide as much information about the existing or planned:
  • Wall partitions — masonry, drywall, glass curtain wall, etc.
  • Floor systems
  • Ceiling systems
• Nonstructural Systems: Other factors of your project play a role in a room’s acoustics. Be sure to describe the existence and characteristics of any:
  • Doors and windows
  • Ducts
  • Transoms and air grilles
  • Unblocked ceiling plenum spaces
  • Piping, electrical devices and fixtures

Sources of noise can vary widely depending on site use and surrounding context. Conducting a noise and vibration survey during the planning process helps to identify the specific acoustic insulation needs for the project; diagram via HRS Services

Performance

• Level of sound control: First describe, in the broadest of terms, what the acoustic insulation is expected to achieve. Do you want to be able to sleep soundly in your bedroom? Need to ensure that the elevator can’t be heard?
• Type of insulation: There are many ways to insulate against sound. If you don’t know what you want, don’t worry – the manufacturer will be able to make good recommendations if you provide structural information. These are the most common forms of insulation:
  • Walls – Gypsum or fiberglass sheeting is applied to or inserted within the wall. A double-leaf wall or sound transmission loss barrier is any wall with two faces separated by studs and filled in with the gypsum/fiberglass insulation.
  • Floors – Fiberglass insulation is installed in the joist cavity, with a resilient ceiling system below the joists.
  • Doors – Should be solid wood or have insulated cores, and should be gasketed to prevent sound from passing between the door and the jamb or sill.
  • Windows – Double pane and/or storm windows reduce sound transmission. Weather stripping helps. Windows facing exterior noise sources should be small and as few as possible. Double-hung windows should be able to be tightly closed.
  • Wiring and piping – Holes through which wiring or conduit passes should be sealed or caulked. Cutouts for electrical outlet boxes should be made precisely so boxes will fit snugly. Holes cut out for piping should be sealed with caulking.
  • HVAC – Equipment should be mounted on vibration isolators to avoid transmission of structure-borne noise. Sound traps or baffles will help to attenuate equipment noise in adjacent ductwork. Fiber glass duct liner attenuates air rush and central equipment noise, and fiber glass duct board combines acoustical/thermal insulation with a reinforced foil-kraft air barrier/vapor retarder.
• Sound Transmission Class (STC): These ratings define how effective a specific material is at insulating acoustics within a structure. A higher STC rating will block more noise from transmitting through a partition or assembly. Local building codes sometimes dictate the level of sound isolation between adjacent dwelling units or between dwelling units and adjacent public areas such as halls, corridors, stairs or service areas. These codes also apply to hotels, motels, apartments, condominiums, monasteries and convents. Be sure to note whether or not your project has STC building code requirements.
• Noise Reduction Coefficient (NRC): A scalar representation of the amount of sound energy absorbed upon striking a particular surface and used to rate general acoustical properties of tiles, baffles and banners. An NRC of 0 indicates perfect reflection; an NRC of 1 indicates perfect absorption. If you know your insulation’s desired NRC, state it.
• Environmental: Many manufacturers use reclaimed and recycled materials, so don’t hesitate to specify any environmental requirements.

Via Bonded Logic

Visit Architizer’s Product Catalog to check out the latest acoustic insulation products.

Does your company manufacture acoustic insulation? Click here to learn more about listing your product on Architizer.

Interested in using Source? Sign up here.

External Links

National Research Council of Canada’s Impact Sound Report
Saint-Gobain’s CertainTeed Noise Control Brochure
www.acoustics.com
Buildipedia’s Article on Acoustical Ceilings
Buildipedia’s Article on Mitigating Elevator Noise in Multifamily Residential Buildings

Top image: example of thermal and acoustic insulation; via Archiproducts