Steel Coating Surface Area Calculator

How the steel coating surface area calculator works

Area per plate = broad-face count × length × width + 2 × (length + width) × thickness in metres. Multiply by plate count. One or two broad faces may be selected; all four thin edges are included. The model does not describe beams or hollow sections.

Coating litres = exposed area × coat count ÷ effective m²/L coverage × (1 + ordering allowance / 100). Whole containers = ceil(required litres ÷ container litres). Purchased litres = containers × container size. Material cost extends the entered per-litre quote over purchased litres and rounds half-up to cents.

Zero plates gives no purchase. Coverage, coat count and extra allowance are entered assumptions; avoid duplicating application loss in both effective coverage and allowance. Holes, welds, roughness, overlaps, contact exclusions and complex shapes are omitted. No coating system, film thickness, corrosion class, surface preparation or service life is selected. Hempel distinguishes theoretical spreading rate from an actual application basis.

Worked example

A 2 × 1 m plate at 10 mm thickness has 4 m² across both broad faces plus 0.06 m² of edges. Five plates total 20.3 m² per coat. Two coats at an entered 8 m²/L require 5.075 L; adding 10% gives 5.5825 L. Five-litre containers require two containers, or 10 L. At an illustrative 12/L, cost is 120. One coat instead requires one container and costs 60.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

• Hempel: theoretical coating spreading rate