Home Insulation: Insulating for Sound
Today’s lifestyle is often a loud one. Modern appliances and amenities coupled with today’s high ceilings and hardwood floors help create beautiful indoor environments, but also contribute to noise levels that impact a family’s quality of life. Improving your home’s acoustic comfort with sound insulation can reduce stress and improve overall health and wellness.
What does insulation do for noise?
Acoustic insulation is one of the best ’quieting’ technologies available. A good noise control insulation package not only increases the comfort of your home but also adds to its value. In fact, one of the most economical ways to improve the acoustic comfort of your home is to install fiberglass or mineral wool acoustic insulation—at the time of construction, if possible.
Noise can affect family health
Throughout dozens of studies, noise has been clearly identified as an important cause of physical and psychological stress—and stress has been directly linked with many common health problems. That means that noise can be associated with many of these disabilities and diseases, which include heart disease, high blood pressure, headaches, fatigue and irritability.1
Understanding sound transmission
The Sound Transmission Class (STC) is a single number rating used to indicate the effectiveness of an entire construction assembly (partition, wall, floor/ceiling) in resisting the passage of airborne sound. The higher the STC rating, the better the sound insulation performance of the construction.
|AUDIBILITY OF LOUD SPEECH FROM OPPOSITE SIDE OF WALL|
|35||Audible but not intelligible|
|45||Must strain to hear|
Recommended STCs for your home
For residential partition walls, the recommended STC depends on the particular type of room. For bedrooms, an STC of 52 is good. Living rooms, bathrooms and kitchens should be a minimum of 55.9.
Considering Impact Sound
In addition to the STC rating which concerns airborne sound, floor and ceiling assemblies are also rated for impact sound resistance. Impact sound is structure-borne sound transmitted when one body strikes another, such as in the case of footsteps and falling objects. A single number, the impact insulation class (IIC), is used to describe impact sound performance. As with STCs, a higher number indicates better performance. The current International Building Code requires a minimum IIC rating of 50.10.
Solutions for acoustic comfort
An easy and economical method for increasing the sound transmission loss of a wall is to install sound absorbing acoustic insulation in the wall cavity. Installing fiberglass or mineral wool insulation batts between rooms such as bedrooms and adjoining bathrooms, or between a recreation room and a den or study will keep the noise level between rooms.
Breaking the Vibration Path
An even more effective way to increase the STC rating is to use resilient channels between drywall and studs or joists. Properly installed resilient channels will break the vibration path, which will help reduce sound transmission. Typically, the drywall is screwed to a flange on these channels – not to the studs. By combining insulation, gypsum board mounted on resilient channel, and two layers of 1⁄2 inch gypsum board on one side, a very good STC rating of 52 can be achieved.2
Where to insulate for acoustic control
Installing sound insulation in certain parts of your house can have a significant impact on acoustic comfort. Key areas for insulation include:
- Exterior Walls
- Interior Walls