When some areas of a floor are machine floated and troweled but other areas must be hand floated, what is likely in the finished surface?

• A. Difference in colors
• B. Uniform texture
• C. Increased hardness
• D. Higher porosity

Answer: (A)

When finishing methods vary across a floor, the surface finish will show differences in appearance, especially color. Machine floating and troweling compact and burnish the surface in a way that exposes cement paste and fine surface sheen differently from hand floating. The areas finished by hand can end up with a slightly different depth of paste exposure, moisture loss, and sheen, which changes how the concrete reads in color once it cures. That contrast is the most recognizable result on the finished surface. Hardness and porosity can be influenced by finishing, but color variation is the most likely and noticeable outcome when some areas are machine finished and others are hand finished.