While you may have your reasons for cutting a trench in a concrete slab, this job can often seem daunting and intimidating. However, cutting a trench in a concrete slab – like any concrete cutting job – requires the right equipment, technique, and of course, the proper safety precautions.

So how can one actually cut a trench in a concrete slab? Worry not, because we’re here to discuss everything you need to know! If you would like to learn more about this, feel free to explore our article below.

Required Materials And Equipment 

Depending on the size of your project, there is certain equipment that you will need in order to cut a trench in a concrete slab. 

For example, if you have a small project where you plan to cut concrete slabs less than 6”, a circular saw with a diamond blade is recommended for the job. Abrasive blades may also work, but it is also likely that you will need to replace the blade several times since they can wear out quickly. Diamond blades are much more reliable. 

Meanwhile, if you have a larger project where you plan to cut a trench more than 3-4 metres, a walk-behind wet saw is recommended. Wet saws are also recommended for indoor work as long as there is enough space to use the saw. Wet saws can also reduce the amount of concrete dust that will be created.

Wearing The Proper Safety Gear

Before carrying out the trench cutting job, it is critical that you wear the right safety gear. First, it is important to protect your eyes. Wearing goggles or other eye protection can help keep your eyes from sustaining damage from concrete debris. Sawing concrete is also very loud, so ear protection is another must.

How To Cut Trench Concrete Slab

Aside from eye and ear protection, ensure that you wear a high filtration dust mask to avoid concrete dust from damaging your lungs. Wearing knee pads and shin guards can protect your legs from concrete debris or accidental contact with the saw. 

Heavy-duty boots and gloves are also recommended to wear as a precaution for extreme situations. Steel-capped boots are commonly used in concrete cutting jobs. This will be helpful in case you drop something heavy on your foot or catch an unexpected sharp edge.

Cutting A Trench In A Concrete Slab

The general process for cutting a trench in a concrete slab is relatively similar across projects of different sizes and scopes. The steps presented below highlight the most common method of cutting a trench in a concrete slab. 

Step 1. Choose The Right Equipment

As previously discussed, choosing the right tools is the first step to this concrete cutting job. Make sure that you choose the right cutting tool depending on the scale of your project.

Step 2. Perform Dust Management

Concrete cutting jobs can be extremely dusty, which is harmful for human health. For example, if the job is being done indoors, use plastic sheeting and duct tape to seal off the space before cutting. This is commonly employed as one of the best ways to manage dust. This will also help protect the rest of the area from being covered in dust as well. 

Step 3. Prepare The Concrete Slab

Make sure that the concrete slab is clear of all obstructions. If the concrete has paint or other markings, it is not necessary to remove it unless it obscures you from seeing the cutting lines.

Once you have cleared out the slab, measure and mark the trench that you will be cutting. Chalk is commonly used to accomplish this. Make sure your lines are as thick and bold as possible.

Step 4. Create A Guide Cut

Once you have set your equipment up and put on all your safety gear, you can begin the cutting job. Generally, most saws can adjust the depth of the saw blade, so adjust the saw in such a way that you can achieve a cut half an inch deep.

Cutting a shallow line will make it easier for the saw and for you to control the saw. Do not cut concrete for more than 45 seconds at a time as the blade gets hot very fast.

How To Cut Trench Concrete Slab

Step 5. Finish Your Cuts

After you have made your guide cuts, reset the depth of the blade according to the depth required. Be mindful of the blade overheating. It is recommended to let the blade cool every 30-45 seconds. Go over the guide cuts slowly and ensure that you maintain consistent control over the cut.

Step 6. Remove Concrete From The Trench

Once you have made all of your cuts, make sure to remove concrete in between the cuts. Sledgehammers are commonly used to break up concrete for removal. However, for bigger jobs, you may choose to use a jackhammer. 


If you need concrete sawing performed safely and reliably, be it commercial or residential, please call us at MEGASAW. We have over 20 years of experience providing quality concrete cutting services all over Melbourne. Our experience is your guarantee!

Please call us today on 1300 920 419 or contact us through our website.