Oct 16, 2014

Fresh Air – Let Your House Breathe

In attempting to conserve energy and reduce our heating costs, we can sometimes make our homes too air tight. In fact, for a house to be healthy, it needs to “breathe”. It needs to expel moisture and other gases from inside and take in a constant supply of fresh air from outside.

When a fuel-burning appliance in your home does not get enough fresh air and fails to completely burn its fuel, carbon monoxide is produced.If ventilation is damaged or blocked, or if you have a powerful kitchen fan, bathroom fan or open hearth fireplace, then carbon monoxide can be drawn back inside the house.

Exhaust fans can compound the problem

Be mindful that the air you exhaust from your home has to be replaced. Powerful exhaust fans in bathrooms and kitchens or open hearth wood- burning fireplaces can actually create a negative pressure inside your home, resulting in a back draft which will draw exhaust fumes from your furnace, hot water heater or other appliances back into the house.

How can you tell if your home is too air tight?


  • The air inside your home is usually stuffy and stale
  • Excessive condensation is dripping down your windows (which could also mean your humidifier is set too high, so check that first)
  • The pilot light on your gas appliance keeps going out
  • A gas flame burns yellow instead of blue (except in the case of a natural gas fireplace)
  • The smell of exhaust gases is present in your home; although you cannot smell carbon monoxide, other exhaust gases do have an odour


If you see any of these signs, contact a certified heating contractor or a building ventilation expert to check your home and correct the problem consider these  solutions:

Air Exchanger
If your home is tightly sealed to make
it energy efficient, consider investing in a professionally installed air exchange system. It exchanges the air inside your home for fresh outside air every 24 hours, without wasting heat.

Direct feed
When renovating or building, consider installing heating systems and appliances that have a direct feed of outside air for combustion, so they do not draw air from inside the home. The combustion chambers are sealed so they are safer and more energy efficient.