How to Float and Finish Concrete for a rough, smooth or broom finish.
Step by step instructions for finishing your cement
Choices of Broom Finish: Smooth, or Rough Broomed... At this point (Following Proper Forming and Screeding) you have the choice of how you would like the top of the concrete to look. Walkways and Drives are usually broomed to a rough finish for the sake of Safety and traction.
You may also need to mark stress lines or expansion joints in the pour, This is done while the concrete is still green after the Screeding but before Brooming... Some people repeat this step after brooming to give the lines and borders a nice smooth edge that has a "framed" appearance.
Before you begin to Broom or float: Test the cement in a non-visible area first: If your brooming looks too rough because the broom digs too deep, then smooth it back out with a float and wait awhile longer. (If you are new to this work, Or you do not have a hidden area to test on, You may use some extra concrete to make a thick puddle beside your work area. (You can use a plastic pan for this if you like) This allows you to practice on and test the cement without marring your work area.
As a foot note on Brooming: It is a little better to wait too long and have the appearance too smooth and be "Lightly Broomed" than get too hasty and have it look Rough and sloppy.
For a Rough texture for walkways etc: Wait until the top of the concrete is starting to get thick and solid, The top is still scratch-able but has just about started changing... then take a kitchen broom and lightly rake the broom over the top evenly and carefully. Like painting a fence, you will want your "Brush Strokes" to be straight and even across the entire surface.
For smooth finish you will need to start floating the concrete soon after the Screeding. Be careful not to overdue the floating as that will cause the pebbles to drop and you can end up with a fragile top layer.
Give it a quick once over to make sure there are no dips or holes... make sure you fix any imperfections left behind by the screeding... then wait until the concrete sets up some before floating again.
Yes it is difficult to wait... but you need to... take a walk... go get a cup of coffee... depending on the cement and time since the Screeding... it may be an hour or so... But be watching the time and check on the concrete... when its time to float it, you will want to get right on it.
When you are ready to float the concrete use 18" or larger squares of a thick plywood to put your knees, toes and hands on. this will prevent you sinking in if the concrete is on the soft side yet... be careful.
Do not corner yourself.
Start at the inaccessible corners and work your way back to the doorway or exit.
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