Cutting Hardie Boards - Short Guide

Installation of hardie boards can’t be termed as cumbersome or too technical to be handled by anyone, but it needs more of physical effort and energy. Having a helping hand is highly desirable and suggested.

Well, the most important activity connected with the instillation of a hardie board is the actual process of cutting it. Many a time people ask for the best technique and tricks to be employed while on such a job. For proper execution of any job you need to have a proper tool. The same job could be executed by using just one simple tool or a set of different tools, each performing a different activity with varying efficiencies. Here’s a list of Hardie tools that may be used to cut different varieties of James Hardie Boards like Hardibacker, Hardie board siding, Hardie plank, and any other kind of cement board or Hardie panel. DuraRock, has a composition different than other James Hardie siding plank products and the outcome of using some of these tools may not be very impressive and efficient.

- Hardie Board Shears

- Circular Saw with Hardie Blade

- 4 degree Angle Grinder with Diamond Blade

- Jig Saw

- Utility Knife

There are good reasons for positioning Hardie Board Shears on the top. Being lightweight and compact they offer the ease of operation and are almost dustless. Hilti is one of the better known producers of Hardie Board Shears and are easily available with hardware stores like Lowes and Home Depot. Though they are expensive, you could get them on rent, but it will be worthwhile to wait for a sale to get them at discounted prices. There is a limitation, though of using these shears; if you work too close to the edges, they tend to crush, crumble and even break the edges. You’ll need to take care of that.

If you are in possession of a basic set of power tools, you would probably have a circular saw with the conventional blade for cutting the board. The problem would be the dust generated by using a conventional blade. You would wish to have a dust collector. That’s how the manufacturers of Hardie boards were prompted to make specially designed blades that do not generate so much of sawdust.

Let’s look at another conventional way of doing the same job of cutting a Hardie board. It can be achieved by using a 40 angle grinder in conjunction with a 40 diamond blade. While doing a perfect job of cutting, you will notice that a diamond tool comes handy for making small but rather difficult cuts needed while working on designs of your windows or for trimming of doors. But, here again the drawback persists: there is an inescapable volume of dust that makes working too difficult and unhealthy too. You would better consider the procurement of a cyclone dust collector. A word of caution! You need to be extra careful while using a grinder for cutting of Hardie board lest it should hit back at you while you were at it.

A jigsaw may work well, but only if you are going to have tight or even circular zigzag cuts. For making long straight cuts you definitely need something better. Your blades will wear much faster while cutting on a Hardie board and it would be good to have them in stock to facilitate quick and prompt replacements.

And of course you do have that option of using a utility knife and a straight edge. Without doubt, that is the cheapest tool you could employ for cutting a Hardie board. Believe me, it works fast and is the simplest instrument that anyone could use for the intended purpose. But, for getting effective results, you should use it mainly for making straight cuts. Simply draw a line, and use your knife a few times to score along the drawn line before breaking the board. This trick works better on a quarter degree board, but does work for a half degree board also.

It is of utmost importance to take all the precautionary measures while working on a Hardie board. Under no circumstances you should venture into any activity connected with its cutting or fixing before you have put on all your protective gear that includes ear plugs, gloves and goggles. The process of cutting should always be in an open and well ventilated area.

You are welcome to share your experiences of cutting a Hardie board. You might have hit across a better way of doing it!


  1. scalping cutter used for milling of plain surfaces of ferrous as well as non- ferrous metals

  2. scalping cutter used for milling of plain surfaces of ferrous as well as non- ferrous metals

  3. The blog is informative..The reasons for positioning Hardie Board Shears on the top is specially informative..

  4. You can use a circular saw or a jigsaw to cut smaller and unusual curves. But for dividing a single board, there is a special fiber cement scoring knife. You just score the board using a meter stick then snap it.

  5. nice share and good work by the houston siding companies relate on this post.