How Radon Gas Be Mitigated in Soil Crawl Spaces?

Few indoor air quality hazards are as silent and serious as radon gas. Found naturally in soil, radon is a radioactive gas that can seep into homes and accumulate over time, particularly in enclosed areas like basements and crawl spaces.

Since it's colourless and odourless, many homeowners don't realize it's there until they conduct a proper radon test.

At Peerless Air, we're dedicated to helping homeowners reduce health risks and improve indoor air quality through professional radon mitigation solutions. One of the most common problem areas is the soil crawl space.

These unfinished spaces beneath homes are notorious for allowing radon gas to infiltrate living areas. Fortunately, we can manage and dramatically reduce radon levels in these environments with the right mitigation strategies.

Understanding the Risk of Radon Gas in Crawl Spaces

Radon gas forms naturally from the breakdown of uranium in rocks and soil. As it rises from the ground, it can enter homes through cracks, gaps, and primarily through unsealed crawl spaces. 

Homes with soil-based crawl spaces are particularly vulnerable because they often lack vapour barriers or concrete slabs that would otherwise help slow the entry of gases.

Once radon enters a crawl space, it can be drawn into the home's living areas due to differences in air pressure, especially during the colder months when heating systems are running and windows remain closed.

Long-term radon exposure is the second leading cause of lung cancer in Canada after smoking. That's why testing and mitigation are so necessary, especially in homes where the foundation includes crawl spaces with exposed soil.

Testing Comes First

Before we install any radon mitigation system, we start with professional testing. This helps us determine the severity of the problem and informs us of the solution we recommend.

In many cases, elevated radon levels are confirmed in crawl spaces that appear dry and well-ventilated, proving just how essential testing is, even if the space looks safe.

Encapsulation and Vapour Barriers

One of the most effective methods of reducing radon entry from a soil crawl space is encapsulation. This process involves sealing the crawl space with a high-quality vapour barrier. 

We install a thick, durable plastic membrane across the floor and up the walls of the crawl space, sealing it around support posts and piers.

Creating a continuous barrier between the soil and the air inside your home helps block radon from entering the living spaces above. This method is especially effective with ventilation or suction systems designed to reduce pressure buildup further.

Sub-Membrane Depressurization

For crawl spaces with encapsulation, we often recommend a sub-membrane depressurization system. This system works similarly to sub-slab systems used in basements.

A vent pipe and radon fan are installed beneath the vapour barrier. The fan continuously pulls radon-laden air from beneath the membrane and safely vents it outside, above the roofline.

This technique prevents radon from building under the home and ensures it doesn't find its way indoors. It's one of the most reliable and long-lasting radon mitigation methods for crawl spaces.

Crawl Space Ventilation Systems

Sometimes, we recommend a ventilation system to dilute and exhaust radon gas directly from the crawl space. This can be done through passive vents or with an active fan-assisted system. 

Increasing air circulation can help lower radon concentration levels, especially when combined with encapsulation.

However, ventilation alone is rarely enough to reduce radon to safe levels. That's why we typically use it as part of a broader mitigation strategy tailored to the property's needs.

Sealing Gaps and Cracks

In addition to installing barriers and ventilation systems, we seal any visible cracks or gaps in the crawl space's foundation, walls, or floor. 

These small openings can allow radon to flow freely into your home. While sealing alone isn't enough to fully mitigate radon, it enhances the overall effectiveness of other systems we put in place.

Why Professional Installation Matters

Radon mitigation is not a one-size-fits-all solution. Crawl spaces vary widely in layout, condition, and accessibility. Our team at Peerless Air evaluates each property carefully before recommending a custom system designed to deliver long-term results.

Professional installation also ensures that the vapour barriers are properly sealed, that fans and piping are correctly configured, and that your system complies with local building codes and radon mitigation standards. DIY approaches may offer temporary relief, but they rarely address the full scope of the problem.

Peace of Mind Through Monitoring

Once your mitigation system is in place, we follow up with radon testing to confirm its effectiveness. We often install continuous radon monitors or recommend periodic testing to ensure levels stay within safe limits. We want homeowners to have peace of mind knowing their living space is protected.

Take Control of Your Indoor Air Quality

Radon is a serious health concern, but it can be effectively managed with the proper mitigation system, even in crawl spaces with exposed soil. At Peerless Air, we bring experience, precision, and a commitment to safety to every radon mitigation project we take on.

If you suspect your crawl space could contribute to radon levels in your home, don't wait. Contact us today for a professional assessment and customized solution. Your family's health and comfort are worth it.