What Is PVC? Pigment Volume Concentration
Pigment volume concentration is the ratio of pigment to binder by volume. Above 45% PVC paints go flat and chalky. Below 15% they go glossy. Here's why.
Most people notice it without naming it: the budget paint in the spare bedroom looks flat and almost soft, while the same brand’s premium line in the hallway looks tighter, denser, slightly sheeny even at the same labeled finish. Same color, same applicator, same coat count. The variable is pigment volume concentration, and it’s the single number that separates a $28 gallon from an $80 one once both are dry on the wall.
PVC is the ratio of pigment to binder by volume in the dried film, written as a percentage. A premium interior wall paint runs around 30–40% PVC. A bargain contractor flat runs 70% or higher. That gap is most of the price difference, and almost all of the durability difference.
How the Math Works
The formula is straightforward. Take the volume of pigment in the dried film, divide it by the total solid volume (pigment plus binder), multiply by 100. Solvent and water aren’t counted because they evaporate.
So a paint with 35 ml of pigment and 65 ml of binder per 100 ml of dry film is 35% PVC. A paint with 75 ml of pigment and 25 ml of binder per 100 ml of dry film is 75% PVC. The reason for that wide range is that “pigment” in the formula isn’t only the colored stuff. It’s titanium dioxide doing the hiding, plus extenders (calcium carbonate, kaolin clay, silica, talc) doing the bulking. Extenders cost a fraction of what binder costs. Cranking PVC up by loading the can with extender is how budget paint hits its price point.
The Critical Threshold
Every paint film has a tipping point called CPVC, or critical pigment volume concentration. It usually lands between 45% and 55%, depending on the binder chemistry and how the pigment particles pack together.
Below CPVC, there’s enough binder to fully wrap every pigment particle and fuse into one continuous film. The wall is sealed, dense, and washable.
Above CPVC, the binder runs out. Pigment particles pack against each other with air gaps in between. The cured film is porous. Light scatters off the rough surface instead of reflecting cleanly, so the sheen drops. Water and oils wick into the film instead of beading on top, so cleaning gets harder. A damp finger picks up loose pigment at the surface. That’s chalking.
Formulators talk about the Λ ratio (PVC ÷ CPVC) to predict where a paint will land. A Λ of 0.7 is a confident, well-bound finish. A Λ of 1.1 is a chalky budget flat. Premium wall paints aim for 0.6–0.8 deliberately.
PVC Sets the Sheen
This is where the conversation gets practical. PVC is most of why a flat and a semi-gloss in the same product line behave differently, and it explains the sheen ladder almost entirely.
| Sheen | Typical PVC | What’s happening at the surface |
|---|---|---|
| High-gloss | 10–15% | Almost pure binder film, mirror-flat, light reflects cleanly |
| Semi-gloss | 15–25% | Dense binder, low pigment loading, washable and tight |
| Satin / eggshell | 25–35% | Balanced — pigment textures the surface slightly, breaks the gloss |
| Matte / flat | 35–45% | More pigment at the surface, scatters light, low sheen |
| Contractor flat | 55–75%+ | Pigment-loaded, porous, chalky, cheap |
A premium wall paint sold as flat will sit at the top of the matte band, around 40–45%. A budget flat sold to a contractor for ceilings sits up at 70%. They both read as “flat” in the can. The contractor flat will burnish, chalk, and fail to wash. The premium flat won’t. Same labeled sheen, different PVC, different paint.
See the sheen guide for the longer version of how sheen is measured and rated. The number on the chip is gloss units; the number behind it is PVC.
Why Budget Paint Runs High PVC
Pigment is cheaper than binder. Extender pigments (the calcium carbonates and clays that bulk the formula without contributing much hiding or color) are cheaper still. A formulator hitting a $25 retail target leans on extender to fill the gallon, because every ounce of acrylic resin replaced with limestone saves real money at scale.
The wall doesn’t lie about it. A high-PVC paint feels soft and absorbent under a finger the day it dries. It picks up scuff marks instead of wiping clean. It burnishes — turns shiny in patches where you’ve rubbed it — because the binder is too thin to resist the polish from repeated wiping. It chalks at the surface within a year in a sunny room. Every one of those failures traces back to a film with too much pigment and not enough resin to lock the pigment down.
That’s also why the same brand can sell a $32 wall paint and an $82 wall paint in identical-looking cans. Most of the gap is binder cost. The expensive can carries roughly twice the resin per gallon and roughly half the extender, and the difference shows up at year three on the wall, not on the chip in the store.
How to Read PVC on a Spec Sheet
The front of the can almost never tells you PVC. Premium manufacturers publish it (or the related Λ ratio) in the technical data sheet — the PDF linked off the product page on a real brand site. Mid-tier and budget lines usually don’t publish it, which itself is information.
A few tells you can read without the TDS:
- Solids by volume is on most TDS sheets. If a wall paint lists 30%+ solids by volume, it’s a binder-heavy formula. Under 25% means you’re paying for water.
- Coverage of 350–400 sq ft per gallon at the recommended mil thickness usually tracks with a well-bound, lower-PVC formula. Coverage of 250 sq ft means the formula needs the extra wet mils to deliver opacity, often a sign the pigment is doing more work than the binder.
- Scrub rating in the TDS — ASTM D2486 cycles to failure — drops off a cliff above CPVC. A premium wall paint clears 500 cycles. A high-PVC contractor flat fails before 100.
Buy paint by the binder fraction. The label calls out the sheen because that’s what the customer asks for. The PVC behind the sheen is what the wall actually gets.