Ventilation requirement for a four-bedroom, three-bathroom, one-kitchen, and two-car garage home is how many CFM?

• A. 350
• B. 450
• C. 500
• D. 550

Answer: (B)

In residential ventilation design, the continuous outdoor-air requirement scales with the number of bedrooms to provide enough fresh air for the occupants. A four-bedroom home falls into a middle category that these common ventilation tables use, which typically amounts to about 450 CFM. This ensures there’s sufficient air exchange for a household that could include several people, helping to dilute indoor pollutants and maintain good IAQ.

Smaller homes or fewer bedrooms would usually map to a lower rate (for example, around 350 CFM), while larger homes with more bedrooms would call for higher rates (around 500–550 CFM for five or more bedrooms). Kitchens and bathrooms contribute to exhaust needs but are generally addressed with specific local exhaust provisions rather than the continuous whole-house rate, which is tied to bedroom count.

So, 450 CFM best fits a four-bedroom home on these typical residential ventilation guidelines.