What are the symptoms of poor indoor air quality, and how can it be improved?

If your home has insufficient air distribution and ventilation, you may find that your home has poor indoor air quality. Insufficient air distribution and ventilation often results in mould, condensation on windows and mirrors, lingering smells after cooking, and chemical smells (from synthetic fabrics, furnishings, household products, cigarette smoke, burning candles, etc.). If your home has poor indoor air quality, you may also observe the following symptoms: sneezing, coughing, congestion and itchy eyes. If your home’s indoor air is too dry then you may find an increase in static shocks, and drier skin and throat.

To maintain good indoor air quality in your home, there must be a sufficient exchange of indoor air with fresh outdoor air. This air exchange will allow mould spores, toxins, odours, excess moisture and stale air to flow out of your home and prevent health problems that can arise from poor indoor air quality. Below are some helpful tips on how to improve the air quality of your home:

• Install ventilation fans – to improve the air quality of your home, install appropriately-sized bathrooms fans and kitchen range hoods. These ventilation fans will help reduce the humidity in your home and prevent mould and condensation problems.
• Use the 10-minute rule – to fully remove humidity, you should run ventilation fans at least 10 minutes after cooking and showering. Running the range hood after cooking will also help eliminate particulates and lingering smells in your home.
• Maintain regularly – range hood filters and bathroom fans should be cleaned once a month to ensure that they ventilate your home effectively and improve indoor air quality. On average, range hoods will work effectively for 10-12 years before they need to be replaced. If you find that your bathroom fan no longer prevents your mirror from fogging, it should be replaced.
• Consider installing a balanced ventilation system –  if you have very poor indoor air quality and want to ventilate your house more evenly, you may benefit from a balanced ventilation system. These systems exhaust stale air and replace it with a consistent supply of fresh air. Heat recovery ventilators (HRVs) and energy recovery ventilators (ERVs) also have heat exchangers to recover some of the heat from exhausted air.

Consider hiring a program-qualified energy advisor to perform an EnerGuide home evaluation and assess your home’s ventilation and air quality needs.

For more information about moisture and air quality problems, visit the Canada Mortgage and Housing Corporation or click here for a booklet.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.