Beware of backdrafting
Typically, supply and exhaust ventilation systems can pressurize or de-pressurize the home. Such a scenario creates issues with moisture in wall cavities and interference with naturally vented combustion appliances.
Combustion appliances such as furnaces, hot water heaters, and fireplaces need air to burn fuel and exhaust combustion gases up the chimney.
A house under enough negative pressure can pull air down the chimney, drawing combustion gases such as carbon monoxide into the house.
This is called “backdrafting” and is a very serious condition that can quickly cause severe injury or even death. Before installing a ventilation system, you should have your home checked to make sure there is adequate make-up air for the fuel-burning equipment.
|Too much negative pressure in a home can cause backdrafting at exhaust points, like a fireplace.|
After a ventilation system has been installed, or after any major structural changes have been made, it is very important to recheck for both backdrafting and radon.
Broan offers selected fans and range hoods that can incorporate a Make-Up Air Damper that provides effective Make-Up Air to ensure a balance of stale air exhaust and fresh air introduction within the home.
If you're upgrading a ventilation system or installing a new one, take time to consider the effects of backdrafting and how that reflects on your ventilation plan.