Concrete is ready for floating when the bleed water sheen is gone and the finisher can walk on the slab leaving about a what depth footprint?

• A. 1/8 inch
• B. 1/4 inch
• C. 1/2 inch
• D. 3/4 inch

Answer: (B)

After bleed water sheen is gone, you’re looking for the concrete to have enough firmness to support your weight without collapsing the surface but still be receptive to the float. When you can walk on it and leave a shallow footprint about a quarter inch deep, that shows the top has stiffened to the right point: strong enough to walk on, yet soft enough for the float to bring the cement paste to the surface and start smoothing and consolidating the cream mix. If the surface is too soft, you’ll leave a deeper imprint and risk marring or gouging the surface; if it’s too stiff, you won’t get a good float, which can lead to skipped areas and roughness. So a quarter-inch footprint depth indicates the right stage for floating.