Single-stage, two-stage and clear coat: how your car is painted

When you look at your car, you see a colour. But that colour is the visible part of a system of several layers, each with its own job. Depending on how the top layers are arranged, we talk about single-stage or two-stage paint. It is not just a technicality: it affects how the paint ages, how it can be polished and how it is repaired.

What lies under the colour

Before any colour goes on, the metal of a new car goes through several treatments at the factory. One of the most important is cathodic e-coating, a dip that covers the whole body, inside and out, with a protective layer against corrosion. On top of that goes a primer or primer surfacer, which smooths the surface and helps the colour look even. The finish is built on this base.

Single-stage paint

With single-stage paint, colour and gloss come from one layer. The same paint provides both the shade and the surface protection. It is common on solid colours such as flat whites, reds or blacks, especially on commercial vehicles, vans and older cars.

• Advantage: it is simpler and quicker to apply.
• Drawback: because the colour is directly exposed, sunlight gradually dulls it. Think of the red that turns pink, or the white that leaves a chalky residue on your hand.

Two-stage paint

With two-stage paint, the work is split into two layers. First comes the base coat, which provides the shade and, where relevant, the metallic or pearl effect. On its own this base is matt and delicate. On top goes the clear coat, a transparent, tough layer that provides the gloss and protects the colour from UV rays, dirt and light scuffs.

Today most passenger cars leave the factory with two-stage paint, in both solid and metallic colours. Metallic and pearlescent colours actually need this system: the particles that create the effect are protected beneath the clear coat.

What it means for looking after your car

• On a two-stage car, most fine scratches and loss of gloss affect the clear coat. A good polish can improve things a lot, but every polish removes a very thin layer, so it should not be overdone.
• If the clear coat cracks or peels, which is common on bonnets and roofs that take the full force of the sun, polishing is no longer enough: it needs repainting.
• On a single-stage car, polishing works directly on the colour and can revive a faded shade, with the same limit on thickness.

What it means for a repair

A repaired panel has to respect the original system. If your car is two-stage, the repaired panel gets base coat and clear coat; if it is single-stage, it is painted single-stage. Each system also needs different preparation: the sanding beforehand, the type of primer and the drying time all change. Mixing systems or skipping steps eventually shows in the gloss, the texture or how the panel ages compared with the rest of the car.

Matching the colour also takes the effect into account: a metallic does not behave like a solid, and sometimes the base coat has to be blended into neighbouring panels, which are then clear-coated in full so no difference shows.

We work with solid and metallic colours in both systems. To find out more, see our colours and finishes and partial respray pages, and if your paint has lost its shine, have a look at polishing and gloss restoration.