25. Pricing and costs: looking beyond the price per kilogram
1. Purchase price is different from project cost
A price per kilogram covers only part of the material purchase. A complete project also includes preparation, repairs, primer, intermediate layers, topcoat, labor, equipment, waste, management and downtime. Different thicknesses and sequences make direct kilogram-price comparisons misleading.
A cheaper material can produce a higher total cost if it needs greater consumption or longer shutdowns. Conversely, a more expensive material may not justify its premium if it does not address the actual project difficulty. Connect the budget to the required outcome.
2. Estimate consumption from thickness and effective film volume
In a simplified calculation, with dry-film thickness in millimeters, mixed density in kilograms per liter and volume solids as a decimal, theoretical mixed-material consumption in kilograms per square meter is approximately thickness multiplied by density, divided by volume solids. This uses the relationship that a 1 mm layer over 1 m² occupies 1 liter.
The formula explains the basic units and excludes roughness, pore filling, tool residue and site losses. Final estimates should use product instructions and trials. Calculate each layer separately in a multilayer system, rather than only the topcoat.
3. An example with explicitly hypothetical inputs
Assume a topcoat requires a 0.20 mm dry film, has a mixed density of 1.20 kg/L and volume solids of 0.90. Theoretical consumption is 0.20 × 1.20 ÷ 0.90, or approximately 0.267 kg/m².
Adding a budget allowance of 10% gives about 0.293 kg/m². “Adding 10%” differs from assuming that 10% of purchased material is unusable; the latter should be calculated using the effective utilization rate.
Thickness, density and solids all affect area cost. Do not substitute weight solids where volume solids are unknown. Quotations should state design thickness, estimated consumption and the loss allowance so both parties use the same calculation basis.
4. Include the application cost of matte and hammered effects
Decorative finishes may require samples, specialist tools, masking, controlled work rhythm and appearance repairs as well as coating materials. Hammered finishes require consistent pattern formation; matte finishes require consistent gloss. Both can impose additional application demands.
Clarify whether a quotation covers materials only, application, or a complete job including substrate repairs. Color adjustments, complex components, night work, phased reopening and subsequent protection can affect price. Meaningful comparisons require a clear scope.
5. Whole-life costs require transparent maintenance assumptions
Whole-life costing may include initial work, downtime, cleaning, local repairs and eventual recoating. State the assumptions transparently. Assuming an unsupported longer life for one product and using that assumption to prove better value is circular.
Compare several maintenance scenarios and identify uncertain inputs. Where conditions vary substantially, start with representative trial zones and monitoring to develop cost data grounded in the site’s own service conditions.