Dry and wet film thickness formula

wet film thickness, dry film thickness

and coating coverage conversion formula

Easily convert and calculate wet and dry film thickness and coverage of coatings applied to substrates. The volume percent of solids in the coating is generally known. Check the coating's directions for use or Material Safety Data Sheet (MSDS).

'Wet Film Thickness' (WFT) = W (this may be known, specified or calculated)

'Dry Film Thickness' (DFT) = D (this may be known, specified or calculated)

Volume percent solids in paint = P (this may be known, specified or calculated)

Volume percent shrinkage reducer added to paint = R

Note that P & R should be expressed as decimals less than 1. For example 72% would be 0.72

Thickness calculation:

No reducing agents or thinners are added to the paint:

If reducing agents or thinners are added to the coating:

Coverage calculation:

From the above equation, the wet film thickness (WFT) for a given dry film thickness (DFT) can be easily calculated. If the wet film thickness is known, the coating coverage in square feet per gallon can be calculated using the following formula:

Coverage in "square feet per gallon" = 1604.17 divided by "Wet Film Thickness in MILS"

(**Above formula is based on a gallon volume of 231 cubic inches)

Example: If "wet film thickness is 10 MILS (0.010")

Coverage is: 1604.17 divided by 10, or 160.417 square feet per gallon.