How the stripe paint estimate works
First calculate painted area = line length (ft) × stripe width (in) ÷ 12 × number of lines × painted fraction. The result is square feet. Next multiply area by wet film thickness (mils) and convert thickness to feet (1 mil = 0.001 inch). The resulting cubic feet are converted to US gallons (about 7.48052 gallons per cubic foot).
For a solid 4-inch-wide stripe extending 1,000 feet and applied at 15 wet mils: area = 333.33 sq ft; ideal liquid paint volume ≈ 3.12 gallons. A 10% loss allowance raises the planning amount to approximately 3.43 gallons. Real-world consumption differs because of equipment transfer losses, surface texture and product requirements.
Can this estimate dashed road lines?
Yes, if you enter the fraction of the route that actually receives paint. For example, 10 feet of paint followed by 30 feet of space means 25% coverage. Do not assume that example is appropriate for your road: follow the roadway agency's actual marking layout.
Can I use the result to prove a DOT specification was followed?
No. Material volume alone does not demonstrate film thickness, line placement, glass bead application, color, retroreflectivity, drying, or regulatory compliance. This is a material purchasing estimator only.
What isn't included?
Irregular markings and stencils, crosswalk bars and arrows (unless represented separately as measurable rectangles), multiple coats, beads, primers, equipment purge, paint remaining in containers, cold-temperature viscosity effects, and unit packaging. Estimate unusual symbols separately from measured area.
Sources & verification
The equation uses standard length, area, film thickness and US-volume conversions, not a purported MUTCD-prescribed paint thickness. For permitted markings, review the current federal MUTCD, especially Part 3; use the project contract and manufacturer's published instructions to choose the actual coating thickness and material.