The amount of extraction (ventilation) you need in your kitchen with two stoves depends on several factors, including the stove's BTU (British Thermal Unit) output, the size of the kitchen, and the type of cooking you do. Proper ventilation is essential to remove smoke, steam, grease, and odors from the kitchen, providing a comfortable and healthy cooking environment.
To determine the required extraction rate, you'll need to calculate the total BTU output of both stoves combined. The BTU rating indicates the heat output of the stoves and is usually mentioned in the product specifications. Once you have the total BTU output, you can use a general rule of thumb:
For gas stoves, it's often recommended to have a ventilation system that can handle approximately 100 CFM (cubic feet per minute) of airflow for every 10,000 BTUs of stove output. For example, if the combined BTU output of your two stoves is 60,000 BTUs, you'd want a ventilation system capable of at least 600 CFM (60,000 BTUs / 10,000 BTUs per 100 CFM).
For electric stoves, a slightly lower CFM rating may be sufficient, around 50-75 CFM per 10,000 BTUs.
Keep in mind that this is a general guideline, and other factors like the kitchen's size, ceiling height, ductwork, and the presence of additional cooking appliances (like grills or deep fryers) should also be considered. If your kitchen has a particularly large or open layout, or if you do a lot of heavy cooking that generates significant smoke and grease, you might want to go for a higher CFM rating.
It's always a good idea to consult with a professional kitchen designer or a ventilation expert to get a more accurate assessment based on your specific kitchen layout and cooking habits. They can help you choose the right ventilation system that meets your needs and ensures proper airflow and air quality in your kitchen with two stoves.