Many homes are now built sealed tight saving you money on utilities especially during cold winters in Calgary. This is great, but something to be aware of is negative air pressure in your home. Negative air pressure occurs when the pressure inside your home is lower than the pressure outside your home. The cause of this issue can be your kitchen hood fan. High CFM fans depressurize your home bringing in cold air through the cracks or if there are no cracks it will bring the air in through the venting of gas appliances such as your furnace, water heater and boilers. Some of the signs you are experiencing this is whistling or odd noises, random drafts of air or doors that are difficult to open or close. A major concern of this is carbon monoxide poisoning. Ways to avoid carbon monoxide in your home is making sure your hood fan has a lower exhaust rate at 100 to 200 CFM. If your current hood fan is higher than 200 CFM it is required by code to interlock the hood fan to your furnace ventilation switch. This can prevent carbon monoxide from entering your home by replacing the air with fresh air. It is very important to make sure you have working carbon monoxide detectors in your home.
