Sheen is a more important paint quality than you might have guessed. It's a measure of the reflectivity of the surface, and although it has nothing to do with color, it determines the visibility of dirt particles that can slightly alter hue. Sheen also determines how easy the paint is to wash. Paints can vary in sheen from matte to high gloss. Satin and semi-gloss are somewhere in the middle; semi-gloss is glossier than satin.

Sheen and Pigment Concentration

Paint sheen is determined by the ratio of pigment, which absorbs light, to binder, which reflects it. The ratio is known in the paint industry as the pigment volume concentration, or PVC.

  • Gloss paint has the lowest PVC -- roughly 15 percent.
  • Flat paint has the highest PVC -- 40 percent or more.
  • The PVC of satin paint is between 30 and 35 percent.
  • The PVC of semi-gloss paint is about 25 percent.

Even though there isn't much difference in pigment concentration between semi-gloss and satin paint, it's a difference that makes a difference. If you use satin paint to touch up a wall painted with semi-gloss, the touch-up will be noticeable after the paint dries, even if the color formula is exactly the same.

Comparing Satin to Semi-Gloss

  • Semi-gloss paint has more binder; hence, it is more reflective and easier to clean. It's a better choice for bathroom and kitchen walls, which are subjected to moisture and abuse and need frequent washing.
  • Although it's easier to clean, semi-gloss paint highlights dirt more readily, and it also shows up wall imperfections. It isn't a good choice for a less-than-perfect drywall taping job.
  • Satin paint works best on hallway, bedroom and living room walls, because it reflects less light and appears more muted than semi-gloss. Stains are more difficult to remove without discoloring the paint.
  • Because of its reduced reflectivity, satin paint can sustain more scrubbing without becoming noticeably duller.

Satin and semi-gloss paints are used interchangeably outdoors, although it still isn't a good idea to mix them. If you choose semi-gloss, don't switch to satin halfway through the job.

No Difference in Price

Don't necessarily expect to pay more for interior paint based on whether it's satin or semi-gloss. Paints formulations involve a number of basic ingredients and additives, and a difference in relative concentrations of pigment and binder doesn't have much effect on price. If a satin paint is significantly more expensive than a semi-gloss from the same manufacturer, it's usually because the satin paint is premium quality.