Radon is a naturally occurring radioactive gas that can enter buildings from the soil beneath and around them. Because it is colourless, odourless, and tasteless, homeowners cannot detect elevated levels without proper testing. In Ottawa, understanding radon and taking appropriate action can be an important part of maintaining a healthier indoor environment.

The Canadian guideline for radon is 200 Bq/m³. Health Canada recommends corrective action when the average annual radon concentration in the normal occupancy area exceeds this level, with faster action recommended as concentrations increase.

This is where radon mitigation Ottawa services can play an important role. Professional mitigation focuses on reducing radon entry and directing the gas safely outdoors.

What Is Radon and Why Does It Matter?

Radon develops naturally when uranium in soil and rock breaks down. Outdoors, it generally disperses into the atmosphere. Indoors, however, it can accumulate, particularly in lower levels of buildings that have contact with the ground.

Radon can enter through cracks in foundation floors and walls, gaps around pipes, sump pits, crawl spaces, and other openings. Since it cannot be seen or smelled, testing is the only practical way to determine whether elevated concentrations are present.

Long-term testing is particularly useful because radon concentrations can change over time. Health Canada recommends using a long-term average when comparing residential radon levels with the Canadian guideline.

When Should You Consider Radon Mitigation Ottawa?

The first step is generally testing your home. If a long-term test shows an average concentration above 200 Bq/m³, Health Canada recommends taking corrective action. The higher the radon concentration, the sooner action should be considered.

For example, a homeowner may complete a long-term test during the heating season and discover that the basement has an elevated radon concentration. Rather than relying on ventilation alone or simply sealing visible cracks, a qualified professional can assess how radon is entering the building and determine an appropriate mitigation strategy.

Mitigation may also be worth discussing when buying a property, completing major renovations, or improving a basement that will be used as a bedroom, office, family room, or other regularly occupied space.

How Does a Radon Mitigation System Work?

One of the most common approaches for existing homes is active soil depressurization. Health Canada describes this as a proven mitigation method that uses a pipe to draw radon from beneath the foundation and exhaust it outdoors. A continuously operating fan creates suction below the building, helping prevent radon from entering indoor spaces.

A typical system may include:

• A suction point beneath or through the foundation
• PVC or similar vent piping
• A radon fan
• An exterior discharge point
• Sealing around selected openings where appropriate
• Monitoring or follow-up testing

The exact design depends on the property's foundation, basement configuration, soil conditions, and existing ventilation. A professional assessment is therefore important rather than installing a one-size-fits-all system.

Why Professional Installation Matters

Radon mitigation is more than installing a pipe and fan. The system needs to be appropriately designed, installed, and checked to ensure it is functioning as intended.

Health Canada recommends using a professional certified through the Canadian National Radon Proficiency Program, commonly known as C-NRPP, for radon mitigation work.

A qualified professional can evaluate the building, identify likely entry routes, select a suitable mitigation method, and explain how the system should operate. After installation, follow-up testing can help determine whether radon concentrations have been reduced adequately.

Health Canada states that a properly installed mitigation system can often reduce radon levels by more than 80 percent, while its September 2026 factsheet notes that active soil depressurization can reduce levels by 90 percent or more in appropriate situations. Results vary according to the property and system design.

Common Radon Reduction Methods

Active soil depressurization is widely used, but it is not the only possible approach. Depending on the property, professionals may consider other techniques.

Sub Slab Depressurization

This method draws radon from beneath a concrete foundation before it can enter the living space. It is commonly used in homes with suitable slab construction.

Crawl Space Mitigation

Homes with crawl spaces may require a different system. The mitigation design can involve collecting radon from beneath the crawl-space floor or membrane and exhausting it outdoors.

Ventilation Improvements

Balanced ventilation systems such as heat recovery ventilators can help reduce indoor radon concentrations in some circumstances. However, Health Canada's current guidance indicates that ventilation is generally less effective than active soil depressurization and requires continuous operation and maintenance.

Sealing Entry Points

Sealing cracks and gaps can complement a mitigation system. However, sealing alone should not automatically be considered a complete solution for elevated radon because radon can enter through multiple pathways.

Why Ottawa Homeowners Should Take Testing Seriously

Ottawa homes can have different foundation types, construction methods, and soil conditions, so radon levels can vary considerably from one property to another. A nearby home with a low test result does not guarantee that another property will have the same result.

Ottawa Public Health recommends consulting a certified radon professional when a long-term test indicates a living or active space is above the Canadian guideline of 200 Bq/m³.

Testing provides information about the actual conditions inside a property, while mitigation provides a way to address elevated levels.

Simon Air Quality for Radon Mitigation Services

https://www.simonairquality.com/services/radon-mitigation-services/ offers radon mitigation and management services for residential homes, real estate transactions, passive radon mitigation, radon-resistant features in new homes, and commercial properties. The company states that its process includes a home assessment, an estimate, and installation by certified technicians when the homeowner proceeds. Simon Air Quality also describes mitigation systems designed to collect radon and safely vent it outside the building.

Conclusion

Radon mitigation Ottawa is an important consideration for homeowners who discover elevated radon concentrations through testing. Because radon cannot be detected through sight or smell, testing should come before deciding whether mitigation is necessary.

When levels exceed the Canadian guideline, a certified professional can assess the property and recommend an appropriate reduction strategy. Active soil depressurization is a widely used approach, while ventilation and sealing may have supporting roles depending on the building.

The most important step is to understand your home's radon level and respond appropriately based on reliable testing and professional guidance. With proper assessment, installation, and follow-up testing, homeowners can work toward reducing indoor radon exposure and maintaining a healthier living environment.