Hardie board is a type of siding constructed of cement fibers by James Hardie Building Products Inc. It is very durable and can withstand extreme weather conditions and insects. To cut this type of siding, use a masonry blade. Masonry blade types include abrasive materials or vented diamond blades that are used for dry cutting. The blades are designed to be used with most cutting tools, including circular, table and miter saws. Reciprocating and jigsaws, which can be equipped with carbide-encrusted blades, are convenient to use when making small or circular cuts in Hardie board siding.

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You can use several types of saws when cutting Hardie board.

Step 1

Measure the Hardie board with a tape measure to match the dimensions needed for the project. Mark the Hardie board's surface with a pencil for reference and cutting purposes. Use a straight-edge tool, such as a square, when marking long lines to ensure precise cuts.

Step 2

Prep the cutting tool, whether it is a circular, miter, table or reciprocating saw, by equipping it with a masonry blade.

Step 3

Place the Hardie board on a stable surface such as saw horses or a workbench. Adjust the Hardie board so the mark made previously is resting over the edge of the work surface to prevent accidental tool blade contact.

Step 4

Place the saw's blade next to the mark on the Hardie board. Squeeze the tool's trigger to turn the power on.

Step 5

Hold the Hardie board firmly in place with one hand and use the other hand to manipulate the saw. Turn the saw off after the cut is complete. Set the tool down after the blade has stopped moving.