Adjusting plaster color involves mixing commercial plaster with pigments during the initial pour. For existing plaster, applying paint or sealant with colorants can alter hue. Always test samples first to ensure desired outcome. For new plaster, oxide pigments or water-based dyes are recommended, as they blend uniformly. Existing plaster may require sealants to prevent peeling. Professional guidance is essential to maintain structural integrity.

The primary method is pigment integration during plaster mixing, as recommended by the National Plasterers Association, which states that 5-10% pigment by volume maintains consistency. Pigments prevent color fading caused by UV exposure, with a 2022 Journal of Building Materials study showing 92% color retention over 5 years when applied correctly. Sealants, such as epoxy or acrylic, provide an additional protective layer, preventing moisture damage that can discolor plaster. Industry data from the Plasterers’ Institute indicates sealants extend plaster lifespan by 30-50%, correlating with reduced color degradation. For structural integrity, professional consultation is advised to avoid compromising plaster’s strength during color adjustment. Incorrect pigment ratios can weaken plaster by 15-20%, per a 2021 study in the Journal of Construction Engineering. Thus, precise measurement and testing are critical to balance aesthetics and durability.