Purpose: This bulletin describes the practice standards with respect to the detection, disclosure, and remediation of radon gas when trading in real estate or providing property management services.

This bulletin applies to real estate brokerages, brokers, associate brokers, and associates.

Radon is an odourless, tasteless, colourless radioactive gas that is the by-product of radium decay. Radium occurs naturally in soil and rock formations. Places with higher than normal radium deposits, such as Alberta and Saskatchewan, have higher radon levels. Health Canada indicates concentrations of radon gas at or in excess of 200 becquerels per cubic metre are unhealthy, unsafe, and are considered ‘maximum acceptable’ in Canada.

Radon is typically drawn up from the earth and into basements, where it can become trapped because of the efficient way homes are sealed from the outside elements.

Prolonged exposure to radon elevates relative lifetime risk of lung cancer. In fact, an increased risk is evident at doses exceeding 100 becquerels per cubic metre, and while 200 becquerels is considered maximum allowable, the formal advice from Health Canada is to pursue ‘As Low As Reasonably Achievable’ radon levels in homes (the ALARA principle).

Radon tends to be a bigger issue in 1, 2, and 3-story single-family homes, condos, and townhouses, and is greatest in the ground and basement floors. Radon levels are typically lower in the upper floors of an apartment building, unless air circulates through the building from below ground or ground level.

The offer, negotiation, acceptance, and condition removal phase of residential real estate transactions rarely provides enough time for a reliable radon test. Reliable radon tests take 90 days or more, should be conducted in winter heating months (October to the end of April), and the measurement device must be specifically placed according to Canadian National Radon Proficiency Program (C-NRPP) standards.

The good news is radon gas is a solvable problem. Mitigation costs vary, but even the most expensive solution is often not more than $2,000 to $3,000 for a typical residential property, and are effectively permanent solutions. It is even possible to solve some radon problems with only a few hundred dollars.

Radon in residential real estate

While a typical residential real estate transaction does not provide enough time for testing for radon, there are still things residential real estate professionals can do to bring radon awareness into the picture.

When representing sellers

When representing buyers

Property management

When representing residential landlords

When representing residential tenants

There is nothing to prevent a tenant from doing their own radon testing and using the provisions under the Public Health Act and Residential Tenancies Act if the radon gas concentrations in the rental premises exceed 200 becquerels per cubic metre. Because legislation requires landlords to provide a safe premises, if the results are high, Alberta Health Services and other provincial government agencies may require the landlord to remediate the property.

Commercial real estate

Radon gas may be an issue for commercial real estate located on the ground floor or below the ground floor.  While the Public Health Act and Residential Tenancies Act may not apply, commercial real estate professionals have the same responsibilities as residential real estate professionals.  Because commercial real estate transactions typically take longer to complete, there will be situations where the offer to purchase and offer to lease are subject to satisfactory radon testing.

Radon testing protocols are different for commercial properties. Consider consulting with a C-NRPP certified professional to determine correct procedures under current federal and provincial laws and guidelines. For example, in accordance with the Radon Awareness and Testing Act (Bill 209), by 2019 it will be mandatory in Alberta to radon test and mitigate, if at or above 200 becquerels per cubic metre, property in which a childcare business, such as a daycare, operates.

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