Finishing concrete is a sequence done at the right moments: screed it level, bull-float it smooth, edge and joint it, wait for the bleed water to disappear, then give it a final trowel (smooth) or broom (textured) finish. Timing matters more than muscle — work it too early and you trap water; too late and it is too stiff.
You have a limited window, and concrete does not wait. Have every tool within reach before the truck arrives: a screed board, bull float, edger, groover, magnesium or steel trowel, and a broom for a non-slip finish.
Screed and float
As soon as the forms are full, strike off the surface with a straight screed board, sawing side to side as you pull it across the forms to level the concrete. Immediately follow with a bull float to push down the stone and bring up a smooth, even paste. Do not overwork it — floating too much or too early pulls water and weak fines to the top.
Edge and joint
Run an edger along the form lines to round and compact the edges so they do not chip. Then cut your control joints with a groover (or saw them later), spaced about 2 to 3 times the slab thickness in feet. See the control-joints guide for spacing and depth.
Wait for the bleed water
After floating, water rises to the surface (bleed water). Do not do anything until that sheen has evaporated and the surface has lost its wet shine. Troweling with bleed water on top is the number-one cause of a dusty, scaling surface. The wait can be 20 minutes or two hours depending on weather.
Trowel or broom finish
For a smooth interior floor, trowel the surface with a steel trowel in overlapping arcs, two or three passes as it firms, for a hard, dense finish. For driveways, sidewalks, and patios, drag a broom across the floated surface instead — the texture gives traction when wet. Then cure it: keep it damp for several days so the surface gains strength.
Common questions
When do you trowel concrete?
Only after the bleed water sheen has evaporated and the surface has firmed up. Troweling too early traps water and causes a dusty, weak surface.
Why a broom finish?
A broomed surface is slip-resistant when wet, which is why driveways, walks, and patios get one. A smooth steel-troweled finish is slick outdoors.
Do you have to cure concrete after finishing?
Yes. Keep it damp (or use a curing compound) for several days. Curing is where concrete gains most of its strength and resists surface scaling.