Radon is a naturally occurring odourless and colourless radioactive gas, may be out of sight but it certainly should not be out of mind when it comes to real estate transactions. In fact, radon is present at different concentrations (depending on the makeup of bedrock or sediment) throughout Canada. If radon levels are too high in a home, the health risks are so significant that it becomes a material latent defect. Radon testing It’s an opportunity to give clients peace of mind as they make the biggest financial decision of their lives.

Radon typically seeps through the ground and into buildings through cracks in the foundation and/or floor slabs, radon can also enter through other openings, like unfinished dirt floors, window casements or gaps around service pipes. Factors like bedrock and soil types, soil moisture level, and seasonal temperature fluctuations also influence indoor radon levels. Concentrations differ greatly across the country, but are usually higher in areas where there is a higher amount of uranium in underlying rock and soil.

Radon concentration levels will vary from one house to another, even if they are similar designs and next door to each other. No matter the age, type of construction or where your home is located, the only way to be sure of the radon level in your home is to test.

Radon levels are constantly changing – hourly, daily, and seasonal fluctuations are all common. If you have tested multiple times and received back differing results, don’t be too alarmed – this is common! There are many different factors contributing to radon levels, but essentially, changes in the air pressure inside and outside your home affect the radon levels of your home.

Radon gas is a naturally occurring radioactive gas found in the soil. As it is a gas, it is continually seeking a lower air pressure area; basically, moving from the soil to the air. Just like water always tries to find the easiest path downhill, radon tries to find the easiest path out of the soil and into the air. When water is running down a steep hill, it flows faster than on a gentle slope. Likewise, radon flows faster when there is a bigger difference in pressure between the high-pressure soil and the low pressure air. This principle of pressure differences is the main driving force that causes radon to enter your home, and also causes radon levels to change.

Typically radon testing performed for the purposes of a real estate transaction are between 3 and 7 days in duration and aiming for 96 hours min of radon testing is best. Running the test for a longer period helps to compensate for any sudden changes in radon levels caused by weather and other factors but may not always be possible. However, the results from the test may still not be a good indication of your normal radon levels, so initial testing should be followed up with long term testing. Minimum of a 3-month test/monitoring is recommended. If readings are over 200 becquerels are recorded it is recommended further testing (12months) and corrective action may be advised.