Question

Please provide a definition of "gloss" as it refers to paint. Rank these paint finishes from lowest light reflection to highest: satin/silk, semi-gloss, eggshell.

Answer

Gloss is the measurement of the light reflectance on a painted surface, and it is measured by a sheen measurement test. This test directs a beam of light at the surface at a specified angle from the perpendicular — usually 60 degrees for mid to high gloss and 85 degrees for flat or low-gloss finishes. The percentage of light that is reflected is measured by a photocell. Of the three gloss types mentioned, eggshell is the least reflective and semi-gloss the most. Normally "flat" paint has a specular light percentage of 0 to 5, eggshell 5 to 25, satin/silk 20 to 35, semi-gloss 30 to 65, and gloss over 65 — all tested at a 60-degree angle.