With the National Building Code (NBC) update scheduled for 2025, indoor air quality issues, particularly the presence of radon, are gaining increasing prominence. Radon, a natural radioactive gas, is a major cause of lung cancer, and its integration into new construction standards marks a crucial step in the fight for safer and healthier homes.

In this article, we examine what this revision means for homeowners, builders, and the entire construction industry.

What is the National Building Code?

The National Building Code is a set of rules and guidelines that establish minimum standards for construction in Canada. Periodically revised, it ensures that buildings meet safety, energy efficiency, and public health requirements.

The 2025 version will introduce reinforced measures for radon management, based on the recommendations of public health and environmental experts.

What will be new in the 2025 Code regarding radon?

1. Mandatory installation of radon barriers
   Every new home will be required to incorporate a radon barrier beneath the concrete slab. This membrane will limit the infiltration of gas from the ground.

2. Preventive mitigation systems
   The 2025 NBC will require the installation of pipes for a passive mitigation system in all new residential constructions. These pipes can be activated (ventilated) if high levels of radon are detected after construction.

3. Improved sealing practices
   Openings in slabs, foundations, and around ducts will need to be better sealed to minimize infiltration.

4. Reinforced regional requirements
   In areas identified as high risk for radon, additional measures may be required, such as active systems from the time of construction.

5. Recommended post-construction testing
   While not mandatory, radon testing will be encouraged in the first few years after construction to validate the effectiveness of the measures implemented.

Why are these changes important?

1. Protecting public health
   Approximately 16% of lung cancer deaths in Canada are attributed to radon. These new requirements could significantly reduce dangerous exposures.

2. Reducing future costs
   Installing preventive measures during construction is much less expensive than adding mitigation systems afterward.

3. Standardizing practices
   With the integration of radon standards into the Code, all new constructions will meet a minimum safety standard, regardless of the individual awareness of builders.

Impacts for builders and homeowners

• Builders: They will need to comply with the new standards, which will involve adapting practices and a slight increase in construction costs. However, these measures will strengthen their credibility and commitment to safe housing.

• Homeowners: New buyers will benefit from increased peace of mind, knowing that their home is designed to limit radon risks.

Prepare for 2025

As the National Building Code 2025 approaches, it is essential for builders and construction professionals to inform themselves and prepare. The implementation of these standards will be a step forward towards a safer and healthier environment for all Canadians.

If you are a homeowner or planning new construction, talk to your contractor or building inspector now to ensure that radon mitigation measures are included in your project. The future of your home starts today, and it must be secure.