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In the realm of home safety, there's a silent intruder that often goes unnoticed, yet poses a significant threat to our well-being: radon gas. Radon is a colorless, odorless, and tasteless radioactive gas that can seep into homes, potentially leading to serious health risks. In this blog post, we'll delve into the basics of radon, its entry into homes, methods of testing, and effective measures for mitigation.

What is Radon?

Radon is a naturally occurring radioactive gas that results from the breakdown of uranium in soil, rock, and water. It belongs to the noble gas family and is chemically inert, meaning it doesn't readily react with other substances. However, its radioactive nature makes it a health concern when it accumulates in confined spaces, such as homes.

How does Radon enter your home?

How Does Radon Enter Your Home?

The primary entry points for radon into homes are through the soil, as it emanates from the ground. Radon can infiltrate through cracks in the foundation, gaps around service pipes, construction joints, and even through well water. Once inside, radon can accumulate to high levels, posing a risk to occupants.

Testing for Radon

Given its elusive nature, radon testing is crucial to determine its presence and concentration in your home. You can use do-it-yourself radon test kits, available at hardware stores or on Amazon (link provides a listing of radon tests), t or hire a professional radon testing service for more accurate results.

Short-term tests are typically conducted for 2 to 7 days, providing a quick snapshot of radon levels. For a more comprehensive understanding, long-term tests ranging from 90 days to a year can be employed. It's essential to conduct tests in the lowest livable areas of the home, such as basements and ground floors, where radon concentrations are likely to be highest.

The following is the test I have purchased and using. It allows for on-demand viewing of the Radon levels. 

Radon levels vary over different periods of the year

Radon levels can vary depending on the time of year due to several factors related to home ventilation, soil conditions, and meteorological influences. Here are some key reasons for seasonal variations in radon levels:

  1. Ventilation Rates:

    • During the winter months, homes are often sealed more tightly to conserve energy and keep the cold air out. This reduced ventilation can result in higher concentrations of radon indoors. In contrast, during the warmer months, windows and doors are more likely to be open, leading to better air exchange and lower radon levels.
  2. Temperature and Pressure Differences:

    • Radon is more soluble in cold air than in warm air. In winter, the temperature difference between indoor and outdoor air is greater, leading to lower indoor air pressure. This can cause an increase in radon infiltration from the soil into the home. In summer, the temperature and pressure differences are typically less pronounced.
  3. Snow Cover:

    • In regions with significant snowfall, the insulating effect of snow cover can influence soil temperatures. The presence of snow can reduce the transfer of radon from the ground into the air, potentially leading to higher indoor radon levels.
  4. Soil Moisture Content:

    • Soil moisture can affect radon levels. Wet soil tends to seal the entry points for radon, reducing its entry into homes. In the summer, when the soil is drier, radon may more easily migrate through the soil and into structures.
  5. Home Heating and Cooling Systems:

    • The operation of heating, ventilation, and air conditioning (HVAC) systems can impact radon levels. During the heating season, the HVAC system may draw in radon-laden air from the ground. In the cooling season, the system may expel indoor air, leading to lower radon levels.
  6. Occupant Behavior:

    • Human behavior, such as opening windows and doors, using exhaust fans, and spending more time outdoors during warmer months, can influence indoor radon concentrations.

It's important to note that while seasonal variations are common, radon levels can also be influenced by geological factors, the construction of the home, and local environmental conditions. Regular radon testing, regardless of the season, is the best way to understand and manage radon exposure risks in your home.

Over a course of 3 months I have been testing and my numbers have varied from 75 Bq/m³ up to 400 recently not that we are entering the winter season, we had new windows and doors installed (creating a better home seal) and when I placed the tester near my suspected entry point. More on my mitigation process below. 

Acceptable Levels of Radon

As of January 2022, radon guidelines and acceptable levels may be subject to change, and it's essential to consult the most recent and authoritative sources for the latest information. However, as of the last update:

  1. Canada:

    • Health Canada recommends that indoor radon levels should not exceed 200 becquerels per cubic meter (Bq/m³). The action level, where remedial measures are recommended, is 200 Bq/m³.
  2. United States:

    • The U.S. Environmental Protection Agency (EPA) has set an action level of 148 Bq/m³. If radon levels in a home are at or above this level, the EPA recommends taking measures to reduce exposure.
  3. World Health Organization (WHO):

    • The World Health Organization recommends a reference level of 100 Bq/m³ for radon in homes. This level is intended to guide national authorities in establishing their reference levels.

It's important to note that these levels are not strict safety thresholds but rather action levels where authorities recommend considering measures to reduce radon exposure. Mitigation measures can be taken even at levels below these guidelines to further minimize the risk of radon-related health issues.

Mitigating Radon

If testing reveals elevated radon levels in your home, taking prompt action is crucial. Mitigation strategies can help reduce radon levels and minimize health risks. Here are some effective measures:

  1. Ventilation Systems:

    • Install a radon mitigation system, such as a sub-slab depressurization system, which prevents radon from entering the home by creating a vacuum beneath the foundation.
    • Use ventilation fans to increase air circulation, diluting radon concentrations.
  2. Sealing Entry Points:

    • Seal cracks in the foundation and walls using polyurethane caulk or other appropriate sealants.
    • Ensure a tight seal around pipes, cables, and other openings in the foundation.
  3. Well Water Mitigation:

    • If radon is present in well water, consider aeration or activated charcoal filtration systems to remove radon before it enters the home.
  4. Professional Assistance:

    • Engage the services of a qualified radon mitigation professional to assess your home and recommend the most effective mitigation strategy.


Radon may be invisible and odorless, but its potential impact on health is substantial. Testing for radon and implementing effective mitigation strategies are crucial steps in safeguarding your home and the well-being of its occupants. By staying informed and taking proactive measures, you can reduce the risks associated with radon exposure and create a healthier living environment for you and your family.

My levels and mitigation process

Over a three month period I tested the Radon levels in my home office where I spend most of my days as of recently the levels have been around 400 Bq/m³, a level that I need to take action at. Lung issues especially hit home with me now after: I got hit by a bacteria - My story of Legionnaires disease.  

There are two primary places where I think the Radon is entering our basement and with these two I will be using the mitigation process of Sealing these Entry Points. 

  1. A ~1.5" hole cut into the basement floor near our furnace where the water drip from the furnace and the air exchanger drips into and a pin crack in our basement floor;
  2. The sump-pump hole located in the cold storage. 

For the water drip hole in the floor, my first thought was to create a seal around the pipe going into the floor and to create a sort of P trap in the line to restrict the flow of air back into the house via the drip pipe into furnace. While I thought this was a brilliant idea, it caused another problem, a vacuum seal on the furnace which caused the furnace not to enter the second heating stage, meaning it would not heat above 19 degrees. 

On I go to my second idea to solve the issue. I will be directing the water drip into a large collection pan and installed in the pan will be a small bulge pump and a float switch. The water will drip into the pan, and when the float switch is engaged, the pump will pump the water from the pan and into the main water drainage of the house. Then seal the hole in the floor with silicone caulking.  

Hole in floor into the ground. Attempt 1 to create a sort of P-Trap. Red is just food coloring as a visual reference Crack in floor sealed.  Sump Pit


Things to fix
Hole in floor
Hole in floor into the ground
Attempt 1 to fix
Attempt 1 to fix with a P-Trap
Sealing cracks
Crack in basement floor
Sump Pit
Sump pump hole


Bulge Pump Water Extraction
Float Switch
Float switch


Pump & Switch
Full system with bulge pump and switch, water dropping in from the furnace. 


Full system, pipe taking water to main water discharge for house.


Sealed floor hole
Basement floor hole sealed. 


Items used for issue 1:

Items used for issue 2:

I will monitor these levels over the next 2 months and if I do not see a significant drop in radon levels in our home, I will move to the step and install a radon mitigation system. 

For the mitigation system, you can install it yourself, its a fairly simple process but you will need a few items that will cost about $1000 and take you about a day if you are handy or you can hire a contractor. Rough cost for a contractor will be about $3000. 

How to Install Radon Mitigation

Rough list of items needed:

  1. Heavy Duty Rotary Hammer
  2. Concrete Hole Saw 130 mm
  3. RadonAway RP145c Radon Fan
  4. RadonAway 50017 Easy Read Manometer
  5. Piping and pipe glue to join it all together

And if you don't believe me about all this, listen to the the Number 1 Canadian contractor, Mike Holmes:

And as a tribute to where I came up with the title of this blog, here's a song for ya.