Grab your tape measure
The following is from
https://www.eastwood.com/garage/calculating-how-much-paint-youll-need-to-paint-your-vehicle/
Here is a primer (no pun intended) on how to calculate how much material you’ll need to paint your project based on these factors. The formula will be:
(
A [Surface Area] +
O [Overage] x
N [Number of coats]) /
C (Coverage) =
V (Volume in gallons)
Factors
Surface area – Most paints will include the total coverage of the product in terms of square feet. This may range from around 100 square feet per gallon to three or four times that, depending on the paint chemistry. Regardless of the actual number, this will be an estimation to apply a single coat of catalyzed paint.
Calculating the exact surface area to painted can be tricky, but you can get a close number by measuring the vehicle in large rectangular blocks, rounding up to the nearest foot for simplicity. You’ll need to measure the areas of each of the major “blocks” to be painted and add them up to get a total. We’ll use our
Chevy C-10 project truck as an example below, calculating only for painting the exterior panels, except for inside the bed.
Bedsides (left and right): 9’ x 3’ = 27 sq ft x 2 sides =
54 sq ft
Lower cab & front fenders (left and right): 9’ x 3’ = 27 sq ft x 2 sides =
54 sq ft
Hood: 6’ x 5’ =
30 sq ft
Roof: 6’ x 3’ =
18 sq ft
Cab back (including cab pillars): 6’ x 5’ =
30 sq ft
Tailgate (inside and outside): 6’ x 2’ = 12 sq ft x 2 sides =
24 sq ft
Total area = 54 + 54 + 30 + 18 + 30 + 24 =
210 total sq ft of surface to be painted. This total must be multiplied by the number of coats for the product (base, clear, etc.) you’ll apply to get a material total for each one.
