Are There Air Quality Concerns with Living Near an Expressway?

May 4, 2020

Here in the Chicagoland area, we have a pretty expansive expressway system. Illinois has the 25th largest land area in the US, but we have the 3rd longest distance of interstate miles in the country. Does proximity to an expressway have a noticeable impact on the indoor air quality in your home?

Let’s first talk about the main components of vehicle exhaust. Standard gasoline-fueled cars give off a mixture of carbon dioxide, NOx gasses, carbon monoxide, hydrocarbons, and particulate matter. There are some other trace compounds that are given off, but these are the main concerns when it comes to what may be affecting your indoor air quality. Vehicles also give off particulate matter from the road surface and tires. Studies show specific risks with being close to roadways, such as reduced lung function, asthma, and more. 

There are some important factors that will play a role in the impact traffic will have on your indoor air quality. The most important being distance from the highway. The further you are from the highway, the lower the likelihood of there being an IAQ concern. Studies have shown the area of highest impact from road pollution is the band roughly 500 meters from the highway. The presence and location of barriers, either a solid structure or “green” barriers like trees will also play an important role. Other dynamic factors, such as the prevailing wind direction and traffic schedules, will also be a factor. Rush hour traffic and the right weather conditions could mean that road pollution is reaching your home when in most other situations the impact is minimal. When it comes to indoor air quality, what factors are important?  Factors such as the “tightness” of the home, location of windows and doors, pressurization, and more all play important roles in the degree to which outdoor air can have an impact on IAQ.

Our company has the ability to assess properties for a number of pollution indicators, both indoors and outdoors. Ideally, we like to monitor these things over a period of time because traffic flow and the weather can change without notice. Measurements over an hour or two may not be representative of the potential hazard in “worse case” situations.
Property values and rent might be less expensive near an expressway. But besides the noise and light pollution, you need to worry about air pollution which can find its way indoors. Maybe the lower living expenses aren’t worth the cost savings.