How Many Range Hood CFM Do I Need

Part of the shopping process for a new cooktop or stove is to consider what kind of ventilation you will need to maintain, or even improve, the air quality in your home. 

The market is flush with ventilation products, and the first step is to understand how many CFM your new range hood or ventilation system will need.

It is important to select the correct CFM for your cooking appliance. If your ventilation product has a CFM rating that’s too low, it will be unable to ventilate the air in your kitchen as needed. Or if your ventilation system has a CFM rating that’s too high, it results in negative pressure, meaning you’ll have to pursue another method to replenish the air. Another drawback of CFM that’s too high is that it can remove air from rooms in your home where you don’t want air to be removed.

First, you need to determine the minimum CFM requirements for your cooking appliance. To do so, consider several factors, including your preferred cooking techniques. If the techniques you use most often include blackening, searing or frying, among other similar methods, you may require a higher CFM rating. The same can be said if you commonly use four or more burners. If your favourite meals require you to do a lot of simmering and sautéing, or you often employ the use of only two burners, then you should be fine with a lower CFM rating.

Often overlooked is that the higher the CFM, the louder the hood will be. This is an important consideration when shopping for a ventilation product, especially if you live in a condo or have an open floor design.

GAS COOKING SURFACE

Most manufacturers publish the British Thermal Units (BTU) rating for each appliance model. BTUs measure the heat output of stovetop burners on gas ranges and cooktops. You can calculate the CFM requirement based on the BTU rating. If you typically cook on high heat and use every burner, just divide the total BTUs by 100, and you will get the CFM required.

The width of a ventilation product should match that of the cooking surface. Ventilation products are typically 30”, 36” and 48” which are also common cooktop or stovetop widths.

INDUCTION & RADIANT COOKING SURFACES

These cooking surfaces produce less heat than gas models. Their CFM requirement for these models is between 200 - 400 CFM, but it does depend on the number of burners and the power.

Some building codes mandate adequate makeup air provisions for the use of ventilation products. Exact CFM requirements are dictated by the installation location and method. Always consult your City Bylaws in addition to speaking with an HVAC professional for the exact requirements in your region.