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Health Issues

Canadians For Properly Built Homes > What We’ve Learned > Health Issues

Newly Built Homes and Occupants’ Health

It’s important to recognize that an improperly built home can have negative impacts on the occupants’ health, particularly in the case of Code violations.  Two areas of particular concern are mould and radon.

Mould: What you should know

According to Health Canada, indoor mould is a significant health hazard. Mould is a fungus, of which there are many types, that can grow in homes and other buildings. It can affect your respiratory system and make asthma worse if you have it. In extreme cases it can lead to cancer. People living in homes with mould and damp conditions are more likely to have:

  • eye, nose and throat irritation
  • coughing and phlegm build-up
  • wheezing and shortness of breath
  • worsening of asthma symptoms

The young, the elderly and people with existing health problems may be more susceptible to the effects of mould. Any concerns should be brought to a medical professional.

Health Canada recommends controlling dampness indoors and cleaning up any mould.

Smell something musty?

It’s not always easy to see the problem as mould can be hidden in walls, above the ceiling or many other places. One thing is for sure – it will be in a damp place. Ceilings, windowsills, bathrooms, laundry rooms and basements are all possible locations where dampness can provide an environment for mould to grow.

Immediate action is important. Mould will begin to grow within 48 hours.

In newly built homes, mould can be the result of Code violations. Inadequate or poorly installed HVAC systems can lead to mould that causes illness.

In 2012, CPBH led a group of homeowners to the Ontario Legislature to bring attention to the problem. That same year, CTV’s W5 did a segment on this issue called “Cold Comfort”. CPBH brought HVAC industry leaders together who ultimately expressed their commitment in a Joint Statement that “properly designed and properly installed HVAC system is critical for home comfort and for the safety and health of occupants.”

Read more about the progress made and the Joint Statement here:

If you have moisture problems and mould in your newly built home, whether the cause is hvac or a crack in the foundation or any other reason, the first thing to address is the health of the people who live in the home.

Read the Health Canada page on mould , the hvac page on this site and the information about dispute resolution .

This infographic from Canada Housing and Mortgage Corporation (CMHC) provides information about possible sources of moisture and mould in a home. While it is intended for First Nations, it is informative.

Your builder, industry professionals, your warranty provider, and the city or municipality may all have a role to play in resolving the mould issues.

Addressing mould problems promptly is important for good health.



Radon Gas: What you should know

Radon is a radioactive gas emitted from the soil and rock. It exists across Canada in varying amounts. You cannot see, smell or taste it, but it can accumulate to high levels in buildings, like homes, and can present a serious health risk to you and your family.

Radon is the second highest leading cause of lung cancer in Canada, responsible for 3,000 deaths each year (Health Canada) and the leading cause of lung cancer in non-smokers (Lung Cancer Canada). 

Whether you are a homeowner, buying an existing home or having a new home built, you need to learn about it and take action if needed. It gets into homes through cracks in the foundation, pipes, wells, basement windows and more. It can also be found in well water.

Builders cannot test for radon before building a home.

According to Health Canada, the acceptable level of radon in the average home is 200 becquerels per cubic metre (200 Bq/m³).

Testing your home is the only way to know if you need to act. November is Health Canada’s Radon Action Month: Buy a kit that measures radon for three months, send the kit to the lab and get results. November is the best time to start testing, so the kit can measure radon in your home during the cold months when windows and doors are most often closed. Health Canada provides links to maps, kit sources and remediation information:


Tips related to Radon: Before signing the contract with your builder for the construction of your home, do your research and take necessary steps, e.g.,  

Ask the builder you are considering purchasing from about:

–       any precautions they use in the construction process, for example:

o    do they install a venting system during construction in the event that radon is detected later? This allows easy installation of the sub slab depressurization system if needed later.

o    do they lay a shield beneath the foundation during construction?

–       if the builder will cover the cost of remediation if needed.

–       whether the warranty that comes with the home covers remediation work if needed.

Get any builder commitments in the contract of purchase and sale.


Tips related to Radon: After taking possession of the home:

–       For a newly built home, Lung Cancer Canada recommends getting your home tested during the first heating season in your home. As noted above, November is Health Canada’s Radon Action Month – and you can get a kit from Health Canada. Older homes need to be tested regularly.

–       If you hire a company to do the testing, to avoid potential for conflict of interest, get the testing and remediation done by two different companies.

–       Reducing the radon in your home is possible and effective – see links above. Sealing cracks in the foundation and installing ventilation systems are common methods: Consult a professional.

–      While remediation may cost in the neighbourhood of $3,000, it is part of the cost of owning a home, so you should plan for it. It saves lives.

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