Does a New Home Still Need Radon Testing?

Many homeowners assume that a brand-new house must be protected from radon. It is understandable: new homes follow modern construction requirements and may include radon-ready features. However, none of these factors confirms the radon concentration inside the finished home.

So, does a new home need radon testing? Yes. New homes can still have elevated radon, and testing is the only reliable way to know the level in your property.

What Causes Radon in Homes?

Radon is a naturally occurring radioactive gas produced as uranium breaks down in soil and rock. It can move through the ground and enter a home when indoor air pressure is lower than the pressure beneath the foundation.

Possible entry points include:

• Cracks in a concrete slab

• Floor-to-wall joints

• Sump pits

• Utility penetrations

• Construction joints

The age of a house does not create or prevent radon. What matters is the ground beneath the home, its foundation, and how air moves through the building.

Why New Homes Can Still Have High Radon Levels

Modern homes are generally built to be comfortable and energy efficient. Better insulation, tighter windows, and reduced air leakage help Manitoba homeowners control heating costs and improve comfort.

A tighter building envelope, however, does not stop radon at the foundation. If radon enters, lower natural air leakage may allow it to accumulate. This does not mean new homes are inherently worse than older homes. It means energy efficiency and radon protection are separate issues.

The building site also matters. Soil, moisture, drainage, foundation openings, and pressure differences can vary from one lot to another. Even homes built from the same plans can perform differently once occupied.

New construction radon cannot be predicted by appearance, neighbourhood, price, or building age. A detector is needed to measure the concentration. Learn more at “How Long Should a Radon Test Be?”

Does Modern Building Code Prevent Radon?

Depending on the location, construction date, and applicable code, a new Canadian home may include radon-resistant features or a rough-in pipe intended to simplify future mitigation. These features are useful, but they do not prove that the indoor radon level is low.

A passive rough-in is not the same as an active soil depressurization system. It may not have a fan drawing soil gas from beneath the foundation, and its performance cannot be confirmed without testing.

The Canadian National Radon Proficiency Program advises that every new home receive a long-term radon test during its first heating season after occupancy. If elevated levels are found, radon-ready construction may make mitigation easier.

Can Neighbouring New Homes Have Different Radon Levels?

Yes. Two new homes beside each other can produce very different results.

Radon concentrations can be affected by differences in:

• Soil and fill beneath each home

• Foundation joints and penetrations

• Sump and drainage systems

• Heating and ventilation equipment

• Indoor pressure and air movement

• How occupants use the home

A neighbour’s result does not determine yours. Radon in Winnipeg homes and other Manitoba communities must be assessed one property at a time. Health Canada notes that building construction, ventilation, entry pathways, weather, and occupant habits can all cause radon levels to vary.

What Does Health Canada Recommend?

Health Canada recommends that homeowners conduct a long-term radon test for at least three months. Longer tests better estimate the annual average because radon levels change over time.

Canada’s radon guideline is 200 Bq/m³. When a long-term result is at or above that level, Health Canada recommends taking action to reduce it. Testing during the heating season is commonly recommended because homes are usually closed more consistently.

Homeowners can use a suitable do-it-yourself detector or hire a C-NRPP-certified measurement professional. Take Action on Radon also provides Canadian testing resources. 

Should You Test a Newly Built Home?

Yes. Testing is worthwhile because:

• Every home has different conditions.

• Radon-ready features do not confirm the indoor level.

• Radon cannot be detected by sight, smell, or taste.

• Long-term testing provides a reliable estimate.

• Mitigation is only needed when results show a need.

For most newly occupied homes, a long-term test is the best place to start. You can book your long term test today online by clicking here

Frequently Asked Questions

Can a brand-new home have high radon?

Yes. The Manitoba Lung Association notes that any home, old or new, can have high radon. Construction age alone cannot predict the result.

Are newer homes safer from radon than older homes?

Not necessarily. Newer homes may include radon-resistant features, but only testing can confirm the concentration inside.

Does a radon rough-in mean the home is protected?

No. A rough-in is a preparation feature, not proof of an operating mitigation system or an acceptable result.

When should I test a new home?

C-NRPP recommends a long-term test during the first heating season after occupancy. The home should be used normally during the test.

Should I test before finishing my basement?

Testing beforehand can be helpful. If mitigation is required, finding it before completing walls, flooring, or other finishes may provide more installation options.

Test the Home, Not the Assumption

A new home may be well built, efficient, and equipped with radon-ready features while still having elevated radon. Modern construction can make future mitigation easier, but it cannot replace an actual measurement.

A professional long-term test gives Manitoba homeowners a reliable picture of the home’s average level. If the result is low, you gain useful confirmation. If it is elevated, proven mitigation options are available.

RadonPatrol provides professional Manitoba Radon Testing with clear results and practical next steps. Schedule a long-term test to learn what is happening in your home.