Pigment colors concrete by coating the cement particles, and there is only so much cement in a mix. So each extra pound does less than the pound before it. Measured across cast chips, the first step down the ladder darkens the concrete about as much as the next two steps combined — the color keeps deepening, but you pay progressively more for progressively less.
What the measured chips actually show
Chips cast at each published step and sampled for lightness. The figures are how many points of lightness the concrete loses moving from one step to the next — bigger number, more visible darkening:
| Moving from | On gray cement | On white cement |
|---|---|---|
| Step 1 to step 3 | 5.1 points darker | 10.3 points darker |
| Step 3 to step 5 | 4.0 points darker | 4.9 points darker |
| Step 5 to step 7 | 3.8 points darker | 4.9 points darker |
- Step 1 to step 3 — 5.1 points darker on gray, 10.3 on white
- Step 3 to step 5 — 4.0 points darker on gray, 4.9 on white
- Step 5 to step 7 — 3.8 points darker on gray, 4.9 on white
The first move is the big one. Going from step 1 to step 3 does roughly as much visible work as the whole rest of the ladder, and it costs two extra pounds per sack where the climb from 3 to 7 costs four.
Where the published range stops
The dose ladder runs 1, 3, 5 and 7 lb of pigment per 94 lb sack of cement — 1.1%, 3.2%, 5.3% and 7.4% of cementitious weight. The hard ceiling is 10%, which is 9.4 lb per sack.
- Above the top step there is no recommendation. The ladder ends at 7 lb because that is where the published range ends, not because 7.1 lb is forbidden — but nothing above it is recommended either.
- Above the ceiling, loading can affect strength, set time and finish. That is the reason the ceiling exists, and it is a concrete problem rather than a color problem.
Nothing is published above the top step. The four steps and the ceiling are the range, and the measured curve above shows the top step still doing real work — so the practical end is the ladder, not a flattening point beyond it. Above the ceiling the cost is certain and the return is not.
Where it genuinely plateaus
The measured curve above runs across the published ladder, which tops out at 7.4% of cementitious weight. The point where extra pigment stops buying anything you can see sits above that.
- Past about 10% of cementitious weight, gains are almost unnoticeable for the range generally. That is the same figure as the hard ceiling, which is why the ceiling is a sensible place to stop for two separate reasons — you stop seeing a return, and above it the loading can start affecting strength, set time and finish.
- Code 203 is the exception, and it is a big one. Its gains flatten at around 2.5% — roughly a third of the way up its own ladder. 203 is a copper phthalocyanine rather than an iron oxide, and it is far stronger per pound, so the upper steps buy very little. The measured chips agree in direction: the move from step 1 to step 3 is about twice the size of every move after it.
The cement is a participant, not a background
The other half of the answer is that you are not coloring a blank. Gray Portland cement has its own color and mutes every pigment, most obviously the bright ones. White Portland at the same code and the same dose reads cleaner and more saturated. So two slabs at an identical dose can be visibly different depths purely because of the cement.
White 205 is the clearest illustration. It has to overcome the gray of the cement rather than tint it, which is why it behaves differently across the ladder from every other color — and why it is the one shade to discuss with Direct Colors before committing a dose.
Supplementary cementitious materials pull the same way: fly ash and slag lighten the finished result, while still counting toward the cementitious weight the dose is calculated on.
If you want it darker, these still work
Once the dose has stopped repaying you, every remaining lever is somewhere else:
- Pick a darker base code at a middle step rather than a lighter one at the top. Depth built into the pigment beats depth chased with quantity, and a mid-step shade is easier to repeat.
- Use white Portland cement where the color needs to be clean and saturated rather than muted.
- Ask the supplier to hold the fly ash down, since it lightens the result.
- Seal it. Sealers, cures and surface treatments generally darken the apparent color, and solvent-based sealers most of all. This is the cheapest depth available and it is often the one people forget before deciding the slab is too pale.
- Put color on the surface. A stain, a dye or a tinted sealer over integrally colored concrete gives depth that no dose can. Pigment for an even base, a topical for the top.
Prove it on two panels, not on the pour
The way to settle this is not arithmetic, it is a pair of panels. Cast the shade you are considering at its published step, and cast the alternative — the darker base, or the white cement, or the same shade sealed — and look at them cured, dry and finished the way the job will be finished. See how to make and approve a test panel. A second panel costs a few pounds of material; overloading a pour costs the pour.
Common questions
Why does adding more pigment stop making concrete darker?
Because pigment colors concrete by coating the cement particles, and there is only so much cement in a mix. Once the cement is coated, additional pigment has less and less left to coat, so it adds cost and risk rather than depth. That is also why the dose is calculated on cementitious weight and not on the total weight of the concrete.
What is the most pigment I can add?
The published ladder ends at 7 lb per 94 lb sack, and the hard ceiling is 10 percent of cementitious weight, which is 9.4 lb per sack. Above the top of the ladder there is no recommendation, and loading above the ceiling can affect strength, set time and finish.
Is there a published point where the color stops deepening?
Not within the published ladder — measured across cast chips, the top step is still darkening the concrete, accounting for roughly a quarter to a third of the total change. The plateau sits above the ladder: past about 10 percent of cementitious weight the gains are almost unnoticeable. Code 203 is the exception and flattens far earlier, at around 2.5 percent.
I want it darker and I am already at the top step. What now?
Change something other than the dose. A darker base code at a mid step beats a lighter base pushed to the top. White Portland cement gives a cleaner, more saturated result than gray. Less fly ash means less lightening. And a solvent-based sealer darkens the apparent color more than another pound of pigment will.
Does the cement limit how dark I can go?
Yes, and people underestimate it. Gray Portland cement has its own color and mutes every pigment, so the cement is a participant in the result rather than a neutral background. White 205 is the clearest case: it has to overcome the gray of the cement rather than tint it, which is why it behaves differently across the ladder from every other color.
Can I get past the limit by staining the surface afterwards?
Yes, and for a really deep result that is usually the answer. Integral color puts color through the body of the concrete; a stain, dye or tinted sealer works on the surface, and the two can be used together. Pigment for an even base color, a topical for depth over it.
What’s Next
- Gray or white cement → White Cement vs Gray Cement: How the Base Changes Pigment Color
- Every shade and its dose step → Concrete Pigment Color Chart
- A shade between two → How to Develop a Custom Shade
- Prove it on a panel → How to Make and Approve a Concrete Pigment Test Panel
- Quantities → Per Cement Sack or Bag
- When it comes out wrong → Concrete Pigment Troubleshooting
- Chemistry by code → Concrete Pigment Chemistry Explained
Direct Colors. Shawnee, OK. Manufacturing the full decorative concrete system since 1997.
