How to Cut a Granite Worktop
Author Chigwell Building & Joinery
Date 02/04/24
Granite is a very popular countertop surface for modern kitchens.
However, if you’re planning on a DIY project that involves cutting granite yourself, it’s important to understand how to best go about it.
Granite is an extremely hard organic material that requires the right tools, skills and experience to cut correctly.
Table of Contents
- Important Facts Before Cutting Granite
- Tools & Materials
- Preparation
- How to Cut a Granite Worktop
- How to Cut Granite in Situ
- How to Cut a Tap Hole in Granite
- How to Cut a Kitchen Sink Hole in Granite
- How to Cut Drain Grooves in Granite
- FAQs
- What's the best tool to cut granite?
- Can I cut granite using a circular saw?
- Can I cut granite using an angle grinder?
- Can I cut granite by hand?
- Conclusion
Important Facts Before Cutting Granite
Should I Hire a Professional?
Cutting a granite worktop yourself is not that simple, even if you have tools for the job.
First of all, granite is a very heavy material, and as a result you will need the assistance of other people in order to handle it.
Moreover, since granite is brittle, it’s prone to breaking if mishandled.
It’s also easy to damage while cutting, and needless to say, since it is an expensive material this is something to consider.
Considering all this, plus the fact that you will need specialist tools, it’s often more practical to leave the job in the hands of a professional.
If you do not have specialist tools you will need to either borrow them or buy them, so it will end up being uneconomical.
Additionally, granite worktops need to be cut very accurately.
Even the slightest millimetre discrepancy could end up making a difference when installing it, because then the cabinets, sink etc may not fit flush or correctly.
Should I Cut the Granite Myself?
Cutting granite properly is not that straightforward.
You will need great precision, and most importantly, the right tools for the job.
You will also need to have a clear layout of the kitchen worktops, including templates.
While it is possible to do the job yourself, many people opt to hire a professional for the job to ensure that it’s done properly.
Tools & Materials
The following tools and materials are required to cut granite countertops:
- Dust mask
- Safety goggles
- Ear plugs
- Tape measure
- Marker pen
- Painter’s tape
- Clamp
- Circular saw
- Angle grinder
- Spray bottle
- Damp cloth
Preparation
You will need to prepare a stable work surface where the cutting will take place, with the granite clamped down so that it does not move.
Worktop templates are a must, so measure and mark lines to guide the cutting in advance.
The lines should be covered with some painter’s tape to protect the granite from possible chipping.
Once you’ve done this, remark the lines on the tape.
Finally, make sure to wear a dust mask and safety goggles before you start the cutting process.
How to Cut a Granite Worktop
Firstly, set up a straightedge guide along the first line that you intend to cut.
While cutting, it’s recommended that you back-cut the granite first by cutting a section of around 2 inches at the finishing end of the line.
You will need to cut slowly and precisely along the cut line, either using a circular saw or an angle grinder.
Make sure that you always move the tool as you proceed along the cut line, but avoid forcing it along.
If you feel that the tool is struggling, it’s best to cut in two passes.
Once you have completed the cutting, let the dust settle and remove the tape. Then, wipe the granite edges with a damp cloth.
You may notice uneven or rough edges which can then be smoothed down with an angle grinder.
It’s recommended to regularly spray the top of the granite with water so as to help minimise the dust produced and cool the blade.
It is also a good idea to stop at regular intervals to apply cutting oil to the drill.
How to Cut Granite in Situ
Cutting granite in situ can be quite complicated.
The complexity of the job will depend on the size and the layout of the granite, as well as on any in-built elements such as sinks.
In such a case it is often more practical to hire a professional for the job.
How to Cut a Tap Hole in Granite
Start by preparing the granite by marking the cut lines. Like the example above, cover the lines with tape.
Then before you begin cutting, put on appropriate protective equipment.
Start by slowly cutting along the lines using a circular saw.
Cutting holes is more challenging as you will need to change the direction of the cutting.
In the case of holes, you will need to drill a hole in each corner of the hole you want to cut.
You will need to start with plunge cuts in order to enter the granite surface with the saw or grinder. For round holes you will need to use a diamond-tipped hole saw.
Press down as gently as you can on the hole drill, pull the trigger, and try to keep firm pressure on the drill.
If you do not push you should get a better result as you will be able to cut more cleanly.
Always use both hands when operating the saw to have maximum control over it as well as prevent any kickbacks or slipping.
It’s important to ensure that any hole that you make is at least an inch away from the edge as otherwise there is a good chance that the granite will break.
How to Cut a Kitchen Sink Hole in Granite
Housing a sink will require you to cut the granite accordingly.
The process is similar to that required to cut any hole in granite, but in this case it is highly recommended that you have a clear template to match the exact dimensions of the sink that will be installed.
Start by drilling a hole in each of the corners of the sink’s outline.
Then make a plunge cut to enter the granite and commence cutting.
How to Cut Drain Grooves in Granite
To cut drain grooves in granite you will need to use a flute wheel.
This will allow you to grind the grooves as well as polish them and get a smoother finish.
This is a highly skilled and challenging task, so unless you know what you’re doing, hire a professional for this job.
FAQs
What's the best tool to cut granite?
A standard circular saw or a wet-cut circular saw are the best tools for cutting granite. The latter is better as it produces less dust.
Can I cut granite using a circular saw?
Yes, in fact a circular saw is the most suitable tool you can use for granite cutting. Granite can be cut either wet or dry. So, depending on what you prefer you can use a standard circular saw or a wet-cutting saw.
Can I cut granite using an angle grinder?
Yes you can, and in fact an angle grinder is more ideal if you need to make smaller cuts.The following is an overview of how to proceed:
- First of all make sure that you have the right cutting blade for the angle grinder. The best is a diamond blade.
- Secure the granite to a stable surface and put on protective equipment.
- Mark the cutting lines, and place painter’s tape along the lines.
- Start by making small and shallow cuts. Then, work your way slowly cutting along the marked lines. Never attempt to cut the whole piece in one go.
- Cool the blade regularly with a wet sponge, and clean the granite with a damp cloth.
Can I cut granite by hand?
Granite can be cut by hand. However, since it is very brittle, hand cutting is not recommended. You should also consider the financial aspect, because you would not want to damage the granite and have to find a replacement. Any mistakes can be very costly.
If however you feel experienced enough to do so, the following is how to best go about it:
- Clamp the granite to a stable surface.
- Mark the cut lines, adding an extra ¼ inch to account for the width of the chisel and blade.
- Hold the chisel’s point to rest against the granite and gently start to tap the head with a mallet.
- Chisel a groove of around ½ inch in depth along the cut lines. Make sure they are perfectly aligned.
- Then, using a diamond-tipped hand saw start to cut, wetting the blade regularly to minimise the dust.
Conclusion
While considering everything, it’s generally recommended to hire a professional to cut granite.
With it being such a fragile and expensive material, any mistake could be a costly one.
If however you are skilled and experienced enough for the job, and have the right tools at your disposal, cutting granite yourself is possible.
But as mentioned above, it carries huge risks.
As long as you take the right precautions and have the right tools, you can carry out granite cutting as a DIY job if you wish.
