You bought a fogger to fog your house and the square ft of your house is 2500 sq ft and one can will cover 4000 cubic ft how many cans will you need to do whole house?

In order to figure that out, you also need to know the height of your ceiling.

The volume of your house is: (2500) multiplied by (the height of the ceilings)

(Sure hope they're all the same, or this simple method won't work.)

The number of cans you need for the whole house is: (the Volume) divided by (4000).

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A slightly easier way, after we did even more of the math for you:

The number of cans you need is: (the height of your ceiling) multiplied by (0.625).

Example: If the ceilings in the whole house are 8-ft high, then you need 5 cans.