To determine the window size required to achieve a ventilation rate of 1,152 cubic feet per minute (CFM) in a 12ft by 12ft room, we need to consider several factors such as the type of windows, the desired airflow rate, and the ventilation efficiency of the windows.

Assuming a standard window type and ventilation efficiency, we can use a general guideline that recommends a window opening size of approximately 10-15% of the room’s floor area to achieve adequate ventilation. In this case, the floor area of the 12ft by 12ft room is 144 square feet. Therefore, the recommended window opening size would be:

10-15% of 144 square feet = 14.4 to 21.6 square feet (Window Area )

To convert square feet to square inches, we multiply by 144. Therefore, the recommended window opening size in square inches would be:

14.4 to 21.6 square feet x 144 square inches = 2,073.6 to 3,110.4 square inches

Window Area = width (5ft) X height (4ft) = 20 sqft

This means that the total size of the window opening would need to be between 2,073.6 to 3,110.4 square inches to achieve a ventilation rate of 1,152 CFM in a 12ft by 12ft room.

It’s important to note that this is a general guideline and the exact window size required may vary based on several factors such as the local climate, the level of outdoor air pollution, and the desired level of indoor air quality. It’s always a good idea to consult with a professional HVAC technician or indoor air quality specialist to determine the appropriate window size and ventilation rate for your specific needs.