What's That Noise?
Due Diligence Noise Study

Unexpected NOISE is a surprise no one wants to discover after buying a home.

Expectations for levels of quiet at night or for noise levels during the day are different for urban, suburban and rural locations.  However, the reality of 24-hour living in a new location can sometimes reveal noisy surprises.  The potential for "buyer's remorse" or regret can arise from unexpectedly noisy conditions that were not disclosed or were not apparent during the viewing of a home for sale.  Disclosure of potential noise may be incomplete or not well-understood during the viewing of a prospective purchase.  The buyer can guard against surprises by performing a due diligence noise study before closing escrow.

If a noisy condition is found, it may serve as the basis for lowering the price offered for the property.
Also, there are solutions to noise intrusion that can be recommended by an acoustics consultant.  Noise mitigation can often lower unwanted noise levels by ten decibels, which is subjectively perceived as cutting the noise level in half.

In California, if you live near the main north/south highways (Route 5 or Highway 101) or near the Union Pacific Railroad, the average and maxiumum noise levels are predictable and can be mitigated in several ways.  There are many factors to consider:  If your property is above or below (uphill or downhill) from the noise source, noise mitigation may be tailored to your position.  The time of day, during commuting hours or when scheduled trains are passing by, can make a large difference in noise levels.

Simple and unobtrusive architectural intervention, 
such as constructing a visually transparent noise barrier wall 
can be effective in reducing noise levels by as much as ten decibels--
the equivalent of cutting the noise level in half.
Intermittent or "unscheduled" noises may also surprise the new property owner:  Neighbors may have dogs that bark uncontrollably when they are at work, or the neighbors may play loud music at the weekend.  If it's a college town, students may have amplified music or street parties on Friday or Saturday night into the early morning hours.

If buyers have questions about noise sources and noise levels near the location where they are planning to buy, objective answers can be provided in a due diligence noise survey.

Actually, the answers are both objective and subjective.  Noise levels are relative to the surrounding "background noise level," and noise levels are relative to one's life experiences and expectations at other locations.  Noise levels are related to what the new homeowner is willing to tolerate, and willing to ignore.  Particular noises that one person finds objectionable are sometimes quite tolerable to others.

Once again, the objective answer is revealed in the due diligence noise survey, in which all sounds / noises are recorded and documented over a carefully selected 48-hour period.  Based on the due diligence study, the prospective buyer can make an informed decision based on facts.

Best to know before you buy.

The best time period to measure noise levels is beginning any Friday at noon, continuously through to Sunday at noon (48 hours).  You will be provided a continuous record of all events and occurrences in and around the property and an accurate record of sound levels through the day and night during the busiest weekend hours.  This may help the prospective buyer make the final decision about a major real estate purchase.
Results of a Noise Survey over a 24 hour period
near a busy four-lane highway and a concealed railroad track
with grade-level crossings and horn-blowing events

In order to accomplish this, two recordings are made simultaneously:

1.  Sound Level:  sound level meter datalogger
2.  Audio:  audio sound recorder

1.  The Type 1 sound level meter is positioned at the property boundary and measures sound levels every 10 seconds over the entire 48-hour period.

2.  An audio recorder runs continuously for the 48-hour period.  Audio recordings are used for the identification of specific sounds (wildlife, birds, sounds of nature vs. cars, trucks, motorcycles, construction, etc.).

The Due Diligence Noise Study
can be provided by 45dB.com


telephone (805)704-8046