Sound is all around us - welcome hums, and unwanted noise, making sound abatement an increasingly important consideration in home design and construction.
Sound Advice
Some sounds we welcome. A favorite song, a baby’s laughter, the comforting voice of a friend. Then, there is unwanted sound, commonly referred to as noise, which is becoming harder and harder to avoid in today’s environment. According to the 2000 United States Census, 30% of Americans complained about uncomfortable levels of noise in their homes and, of those, nearly 40% found the problem severe enough that they wanted to change where they lived.
One of the primary sources of environmental noise has always been transportation. In fact, ancient Rome banned chariots from driving at night because the din of their wheels on the streets disturbed the peace. Of course, roadway traffic has grown exponentially since that time and today we also have the added sound of air and rail traffic. Machines contribute to the problem as well, especially with the trend of adaptive reuse bringing residential properties to industrial areas.
It has literally become an unhealthy situation with long-term physical and psychological consequences, one that the Southern Medical Journal described as a “manmade plague of environmental noise from which there is virtually no escape.” And, as a result, sound abatement has become an increasingly important consideration in home design and construction.
Many aspects of a building, such as its area, geometry and landscaping, can affect sound infiltration. Construction techniques, like staggered stud walls and using resilient channels can prove very effective. However, according to Wayland Dong, an Associate Principal with Veneklasen Associates, one of the world’s premier acoustical engineering firms, the most important component is getting the right windows.
The type of unit, its materials and installation all contribute to its performance, but the window’s glass has by far the greatest influence on its ability to reduce sound transmission. The number of panes, their thickness and the distance between them all make a difference. Usually, more is better in each category. There are exceptions, however. Andersen® E-Series products are a good example. Their floating glass stop allows for customized combinations of glass thicknesses and space between panes, which lets them minimize resonation and deliver high ratings for sound control.
The most common measurement of a window’s ability to block sound transmission, “sound transmission class” (STC), designates loss of airborne sound between 125 Hz and 4000Hz. A newer standard, “outside inside transmission class” (OITC) is gaining popularity. The OITC rating covers a wider range of sound, 80 Hz – 4000 Hz, which includes the lower frequencies generated by traffic and other exterior sources. For this reason, OITC is often a better reference for a window’s performance.
Window manufacturers that excel at sound abatement will make a point of publishing performance ratings for their products. You can find this information for most Andersen® windows and patio doors here. And, if you have additional questions, or need assistance with a project where environmental sound levels are a concern, contact us at ArchitecturalServices@andersenwindows.com.