If a foreman notices color mismatch across a floor, what underlying cause is most likely?

• A. Difference in colors
• B. Concrete mix ratio errors
• C. Improper formwork
• D. Excess moisture

Answer: (A)

Color uniformity in a slab comes from having the same materials and batch characteristics across the entire floor. When you notice a color mismatch, the most likely cause is that different pours came from different batches, meaning variations in cement content, water-cement ratio, aggregate type/color, or pigment from one area to another. These small differences show up as lighter or darker patches once the surface cures. Other factors like excess moisture can change shade, but they tend to affect areas more uniformly rather than creating a patchwork of tones. Improper formwork mainly affects texture and edges, not overall color consistency.