Hardiebacker cement board is a durable water and mold resistant cement board. Easy to work with but you have to learn how to cut it safely and easily.
Once a deep groove is scored all you have to do is put your knee against the board with the groove facing away from you and snap the hardie board.
To cut square holes or notches in hardiebacker cement board use a disc grinder with a stone grinding disc. Plundge cut each carefully cutting as close to each corner as possible. Then use a jig saw to finish cut each corner. Again eyer protection and a mask are mandatory.
This usually ends up with a pretty straight cut which is perfect for most construction jobs.
If you only have a few cuts to make you could even use a circular saw or table saw. Both will easily cut the Hardiebacker but but will create a huge amount of dust. Be sure to wear eye protection and a mask.
Outdoor Chess Board made from ceramic tile and Hardiebacker cement board.
If you need a cleaner straight cut a tile saw or wet saw works well. These saws will easily cut the hardiebacker cement board and will not create much dust.
The easiest method to cut hardiebacker cement board is to score a line with a razor knife. I like to use a plexiglass knife because it seems to stay in the groove better and it easy to apply extra pressure to assure a deep groove.
How to Easily Cut Hardiebacker Cement Board.