Does Your Home Suck? Keep it Fresh!

VENTILATION – How to Breathe Easy in your Home.

Most people don’t think about the air pressure in their house, or more accurately, the difference in pressure within the house  relative to the outdoors. But pressure affects airflow and the movement of dust, moisture, gases, and smells; in other words, your indoor air quality (IAQ).

You, the resident, have the most to lose or gain in controlling airflow in your house or condo. Become your home’s expert – learn how the air moves around your home !



Between 1986-1990 many new homes were built with increased vapour/air tightness, however due to the lack of understanding at the time, ventilation to compensate for the tightness was not put in.

Lower air pressure in the house relative to the outdoors can promote incomplete combustion of gas/wood burning appliances (furnace, water heater, fireplace) therefore carbon monoxide levels could be a concern.  

Furnace draws combustion air from house

Furnace draws combustion air from house

Areas of your house with very little air circulation can allow excess humidity to form which can lead to mold.


Go through your house and make a list of air controls using the AIRCHART table below as a starter guide.

As you walk through, check to see if kitchen fans actually discharge indoor air to the outside or do they just pull it through a filter and blow back into the kitchen. 

Stove with hood fan

Stove with hood fan

Check the suction of a fan or return duct by putting an 8.5 x11 piece of paper on the grill. Locate exhausts on the outside and check for signs of air movement. 

Do you have an HRV(Heat Recovery Ventilator)? Most new houses come with one. Read the manual and learn how to use the controls and clean the filters.

If you have a forced air furnace/central air, figure out which registers are pushing air into the room and which ones are pulling air back to the furnace (“returns”). Airflow in these registers or ducts can often be adjusted with dampers they come equipped with for temperature comfort. Ensure furniture does not block any grilles.

See also my article about changing filters.

Air Chart


Unless you have an HRV (Heat Recovery Ventilator), if you have fans that exhaust only – the house SUCKS!


In areas where you make smells and moisture – if you have a fan, USE IT!   

If any part of the house gets stale or stuffy, open windows on different levels and different sides of the houses to get a breeze going through.    This is called cross ventilation, and  is most useful during spring and fall when you are less likely to have the heat or cooling on to blow air around the house.   You will find through experience that certain windows or combinations of windows will vent better than others.   

Casement window

Open to let hot stale air out

During one of my home inspections, I will walk around with you to show you how the ventilation systems work, point out any problems or concerns, and my report will have more background information for you.


basement window – use to let cool air in

Maximize your comfort by managing your airflow – MAKE YOUR HOUSE BREAK WIND!