How to Cleanly Cut Cement Board

Step 1 – Choosing Tools

Depending on the cuts you will need to make and the size of your cement board, you will need to make sure you have the right tool on hand for the job. If you are cutting straight lines and your cement board is smaller than a 4-foot by 4-foot square, a table tile saw is your best option. The saw’s guide will make sure your cuts are straight, and with an extra set of hands, cuts are made quickly and easily. For larger pieces of cement board, use a hand-held circular saw. Use a jig saw for cut-outs and curved cuts.

All of these tools are available at your local tool rental outlet. Make sure that you use either carbon or diamond-tipped blades to cut cleanly through the cement. Tell the sales staff that you are cutting cement board and will be using water, this way they can ensure that you have the proper tool for the job.

Step 2 – Preparing Work Area

With cement dust and chalky water flying from your saw blade, cutting cement board is very messy. Always have a tarp underneath your work area to catch dust and water, speeding up your cleaning time. If you are working inside, make sure your work area is sealed off from the rest of the house, keeping dust to a minimum. When working outside remember that dust and water will stain the area where they come out of the saw, and you will want to protect this with a tarp.

Step 3 – Marking Your Cut

For straight cuts, mark your cement board as you would a sheet of plywood. Measure off your distance and use a square and straight edge to make sure you line is marked properly. For circular cuts, hammer a nail into the center of your cut, measure a string to the cut-outs radius (half the size of the opening) and tie one end to the nail and the other to your marking pencil. This will give you a perfect circle to your desired size. For odd shaped cut-outs, make a template using cardboard first, then trace it on your cement board.

Step 4 – Wetting Down

Before cutting, use a bucket of water and sponge to wet your cement board down. You will want the surface to be wet without being sloppy. Wetting your cement board will keep the amount of dust down while you are making your cut.

Step 5 – Making the Cut

Using a table saw is the easiest option. Set the guide rail to your desired measurement and make your cut. Using a hand held circular saw is also straight forward; remember to take your time making the cut to ensure it is straight. When cutting in the center of your cement board, drill a pilot hole first to be able to insert your jigsaw blade. Remember your saw blade is 1/8-inch thick and cut accordingly.

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