Mottling Posted on 7th December 201516th May 2021 by ThePD (The Project Definition) Mottling is a condition of spotting with patches of colour that is the act of colouring with areas of different shades. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Construction and tagged painting. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.