Indoor Air Quality in Homes
Remodeling Your Home? Have You Considered Indoor Air Quality?
Combustion Appliance Backdrafting
Regardless of what part of the house your remodeling project takes place in, there are good work practices that you can use to help minimize or prevent indoor air and other indoor environmental problems. Read more about Good Work Practices.
In general, you should address the following issues when remodeling your home.
Radon |
Lead |
Moisture Control |
Ventilation |
Asbestos |
Combustion Appliances |
Air Ducts |
Energy Efficient Improvements |
Pest Control |
Painting |
Volatile Organic Compounds (VOCs) |
Read about Best Practices
As we exhaust air from our homes, and as air naturally leaks out of our homes because of wind or the stack effect, it is replaced by outdoor air. If we exhaust a lot of air, we can depressurize the home. Sufficient depressurization can actually pull air and combustion products back down a chimney or any flue, such as that of a gas water heater, and into the house. Because of the harmful substances, such as carbon monoxide, in combustion gases, this depressurization can create a very dangerous situation.
Forces working to depressurize a home include those shown in the figure below, bathroom exhaust fans, kitchen range hoods, and clothes dryers. Other forces not shown in the diagram include the fireplaces, leaky return ducts near combustion equipment, leaky supply ducts outside the conditioned space, wind, and the stack effect (warm air rising in a building tends to depressurize lower areas). If these forces are great enough, they can work to suck air and combustion products back down the chimney or flue and into the house, as shown by the red arrows in the diagram.
![Combustion Appliance Backdrafting](images/backdrafting.gif)
There are steps you can take to prevent backdrafting.
Read more about combustion appliances.