Coatings can be applied by brushing in order to protect surfaces against humidity and chemicals. All products should be thoroughly mixed by stirring before application. Normally undiluted varnishes should be brush applied in a single coat and produce a homogeneous film build. Drying is done either by air at room temperature or up at temperatures up to 90°C.

Products typically used for brushing are designed to be air-drying and as such product containers should remain closed and sealed before and after use to prevent evaporation of the solvents and undesired reactions owing to oxidative curing.