by Ron Joseph
October, 2003
Calculating Paint Coverage
Q. How do I calculate the amount of paint in gallons necessary to cover
a part if I know, the amount of mills to apply and the sq ft of the part?
A: It is very easy to calculate theoretical paint coverage. The equation is
as follows:
Coverage (ft2) = 
1604 x Gals used x %Volume solids x %transfer efficiency 

Film thickness (mils)

Where 1,604 is the number of sq. ft. that a solid gallon will cover at a thickness
of 1.0 mils.
Example:
What is the coverage for 1 gallon of paint with 52% volume solids which is applied
by spray with an approximate transfer efficiency of 30%? The dry film thickness
of the applied coating is 1.5 mils.
Coverage (ft2) = 
1,604 x 1 gal x 0.52 x 0.3


1.5 mils

Coverage (ft2) = 167 ft2.
You can usually get the volume solids of the coating from a technical data
sheet, but you must guess at the transfer efficiency.
By manipulating the equation you can now figure out the number of gallons required
to do a job if you have the remainder of the information.
