Why is proper curing important for plaster?

• A. It prevents premature drying, reduces shrinkage cracks, and ensures bond and strength
• B. It speeds up drying
• C. It changes color
• D. It makes surface smoother

Answer: (A)

Proper curing keeps plaster moist and at a suitable temperature as it sets. The plaster hardens through hydration, which requires water to stay in the material long enough for the chemical reactions to complete. If it dries out too quickly, water leaves before hydration finishes, causing shrinkage and cracking and weakening the bond to the substrate. By maintaining proper moisture and conditions during the early cure, you reduce shrinkage cracks and promote a strong, durable bond and overall strength. This isn’t about speeding up drying, changing color, or smoothing the surface; those effects come from other factors, not the curing process.