Ordering colored concrete by the truck is the one pigment job you cannot re-do. Get the quantity wrong and you have a driveway in the wrong color. This is how to calculate it properly before the truck leaves the plant.
A stamped front porch poured in Kohl Gray integral color.
Step 1 — find the PSI, or sack mix
Most slabs are 3000 or 3500 psi, and that figure represents how much cement is in each poured yard. Ask the ready-mix company before anything else. The higher the psi, the more pigment is required to hit the same color on the chart, because there is more cement to color. The calculator covers 3000–6000 psi.
Step 2 — ask about fly ash
Suppliers substitute fly ash for cement at rates commonly between 15% and 40%. There are structural reasons for it, but for color it is a problem: more fly ash means a lighter final slab and much less predictable color. Ask for a mix at around 10% fly ash, and no more than 20%.
Step 3 — calculate by the yard
The number of yards decides the pounds of pigment. Run it through the truck-pour calculator against the color you want from the chart. If more than one truck is involved, the same amount of pigment and water goes into each — otherwise the loads will not match and the joint will show forever.
Step 4 — have the plant add it
What's Next
- The fundamentals → Integral Color Concrete
- Test first → Pigment Sampler
- Other surfaces → Cement, Stucco, Grout and Overlays
- Sealing → The Best Concrete Sealer
- Applying stain outdoors → How to Apply Outdoor Concrete Stain
- Choosing a sealer → The Best Concrete Sealer
- Prefer a reactive, mottled look? → Acid Stain Colors Guide
- Shop → EverStain™ Kits · Trial Kits
Direct Colors. Shawnee, OK. Manufacturing the full decorative concrete system since 1997.
