Why is timing critical between finishing steps?

• A. To prevent tearing, laitance formation, surface crazing, or pull-out of cream
• B. To maximize surface hardness
• C. To reduce curing time
• D. To save material costs

Answer: (A)

Timing between finishing steps matters because the surface of new concrete is always changing as it sets. You want the surface at just the right plastic state so finishing tools don’t pull out the cream or disturb the paste. If you finish too soon, the surface is still very soft and contains free water and slurry; a finishing pass can drag up the creamy cement paste, push water to the surface, and pull away laitance, while also risking tearing the surface. If you wait too long, the surface may have stiffened enough that the next finishing pass gouges or crushes it, leading to crazing or other surface defects. Matching the timing to the concrete’s plastic state helps produce a clean, dense, smooth finish without laitance, tearing, or cream pull-out. The other options miss the central point: timing does not primarily maximize surface hardness, shorten curing time, or save material costs.