How loud is too loud? It's hard to tell. Since 1981, U.S. noise regulations have been handled at the state and local levels, making it tough to keep track of laws, and many jurisdictions leave it to complainants to determine when noise—whether from a neighbor's dog, a nearby wind turbine, or a construction site jackhammer—is inappropriate. And new housing isn't really addressing the issue of noise pollution, says Les Blomberg, executive director of the Noise Pollution Clearinghouse. As proof, he cites the U.S. Census Bureau's American Housing Survey. According to the 2007 survey, of the 33 million units where traffic, neighbors, or the general neighborhood was considered too noisy, 3 percent were built in the previous four years— and new construction accounted for 5 percent of all the units surveyed. Blomberg notes that many sound-dampening solutions can be made up front if architects work with acousticians, adding, "it's orders of magnitude cheaper than fixing the problem later." Sound advice.

No. 1
The rank of noise in the 2007 American Housing Survey as a “bothersome neighborhood condition,” putting it atop litter or housing deterioration; poor city or county services; undesirable commercial, institutional, or industrial facilities; and everything else.

The percentage of units in the 2007 survey where street or traffic noise was considered bothersome. (Total units surveyed: 110.7 million.)

4.4 million
In the 2005 survey, the number of housing units (out of 108.9 million) where street or traffic noise was such a problem, residents wanted to move. The question was dropped in 2007.

30 decibels
The noise level of a whisper. The American Wind Energy Association says noise from most wind farms rises just above this level at a distance of 750 to 1,000 feet.

80 decibels
The noise level that can trigger an increase in aggressive behavior, according to the World Health Organization.

110 decibels
The noise level of a jackhammer.