Floating and toweling a concrete slab too soon can cause which problems?

• A. Dusting and Crazing
• B. Cracking Only
• C. Scaling Only
• D. Color Variation

Answer: (A)

Finishing a concrete slab too soon often creates a weak, powdery surface and tiny surface cracks. When you float and toweling while the surface is still plastic or overly wet, you push down the cream and seal in moisture, which can cause cement paste to rise to the surface and form a dusty, powdery film—dusting. At the same time, the surface dries faster than the interior, leading to plastic shrinkage cracks that appear as fine cracking across the top, known as crazing. This combination is a common result of premature finishing because it both compromises the surface texture (dusting) and creates microcracks (crazing). Other issues like scaling or color variation relate to different conditions (cure, moisture loss, or pigmentation) and aren’t as directly tied to finishing too early, while cracking alone doesn’t fully capture the powdery surface problem described.