Source: The Great Interpretation of Dreams (Ibn Sirin)
Gypsum in a dream indicates stability of affairs and righteousness in religion. Plastering the house indicates covering and protection from enemies.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
Gypsum indicates a hypocritical man. Working with it indicates falling into heresy.
Source: Signs in the Science of Expressions (Ibn Shaheen)
Gypsum is interpreted as goodness. Whoever sees himself plastering his house will attain goodness.