Written by Steffani Cameron and Bob Vila | Updated at 2:40 PM, December 29, 2020

Whether you want to create countertops or expand sidewalks, cutting concrete yourself may not be as difficult as you think. Cutting boards thicker than 6 inches is best left to professionals, but anything less than 6 inches (including the depth of most concrete walls, terraces and sidewalks) can be cut by a DIYer with the right equipment and proper expertise.

Any convenient homeowner who wants to cut concrete needs a key tool: a diamond blade. Although abrasive blades can cut concrete, they wear out quickly and may need to be replaced multiple times during the course of a project. Abrasive blades can cause you to "force" the saw, which is a dangerous move that can cause the saw to lose control and suffer potentially life-threatening cuts. Don't take risks; instead, invest between $30 and $55 for diamond blades (see the example on Amazon).

Regarding safety issues, please note: All the protective equipment listed below are required. The filter mask prevents you from inhaling concrete dust, which can damage lung tissue, which can lead to lung cancer and silicosis. On the other hand, knee pads and shin guards can protect your legs from injury.

An extension cord protected by a ground fault circuit interrupter (GFCI) not only protects you from surges, shocks and overloads, but the waterproof exterior design can also withstand rain and any other hazards caused by contact with water. The manufacturer recommends plugging it into a power source and then, if necessary, plugging in an indoor/outdoor extension cord from there. (Although GFCI cables can be three times the price of ordinary extension cables, they are worthwhile for people who often work outdoors.)

Finally, if you are working on a large project that requires cutting more than 7 feet, please consider renting a "walk-behind" wet cutting saw instead of using diamond blades. Although the rent is expensive (approximately $100 per day, plus the blade wear, the cutting depth is close to 7 inches) and heavy to use, the wet saw will ensure the straightest and deepest cut, and the cost is much lower. The overall work is no chisel required Engraving, without hammering, and repeated shallow cuts. You pay for the degree of machine and blade wear, in units of 1/1000 of an inch, and charge accordingly.

These instructions on how to cut concrete focus on smaller projects done with diamond blades.

Choose the type of blade you prefer to work with: dry cut diamond or wet cut diamond. The former uses a circular saw or a hand-held cutting saw, but you need to moisten the concrete to reduce the flying dust during cutting. On the other hand, a wet cutting blade requires constant watering of the blade-this can be achieved with most tools, but it is easiest to use when you rent and use a suitable "hand-push" concrete cutting saw. By renting this job-specific saw, you can also get a greater cutting depth than using a circular or hand-held cutting saw. For example, a 7-inch circular saw can only cut 2-1/4 inches deep, which means you need to use a sledgehammer to remove the rest of the concrete; on the other hand, the 14-inch wet cutting blade connected to the concrete cutting saw Allows you to make clean cuts of 4-5/8 inches.

Prepare the work area to prevent concrete dust from entering your home. If you are working in a basement or garage, put a shading cloth on any door; if you are outdoors, make sure to close all nearby windows. If it is close to any air inlet, put a tarp or plastic sheet on it.

Use chalk line (suitable for long, straight edges) or chalk to mark the location to be cut on the concrete slab. Apply the thickest line possible. Ideally, you will drop a drop of water on the concrete while cutting to keep the dust in the air to a minimum, and you don't want the lines to disappear.

Take all necessary personal safety precautions: wear heavy clothes, shin guards, knee pads, and steel-toed boots, and protect your eyes, ears, and face. Always wear a suitable filter mask. If you use an electric saw instead of a pneumatic saw, plug the GFCI-protected extension cord into the power source to eliminate surges, shocks and overloads, as well as any dangers caused by using electric tools near the water.

If possible, place a garden hose to distribute the water droplets directly to the location where you will be cutting. When working on flat, level items such as patio slabs, extend the hose to the work area and divert the water to a trickle to keep the surface moist. Hold the hose in place so that a steady stream of water flows through your chalk line.

If you are engaged in vertical work, such as cutting concrete retaining walls, using water can be tricky. Ask a friend to spray water on the concrete slab at work, or do not perform this step at all. Without water, you will only have more dust and need to run the saw in the open air between cuts to cool it down.

Starting from one end of the cutting area, whichever side is easiest for you, place a "guide plate" (any 1"-scrap wood as deep as the cutting line) along the outside of the chalk line.

When the saw is still fully closed, use the depth lever or knob to set the depth of the saw blade (refer to the user manual for instructions) so that it can cut up to half an inch deep. This will give you better control of the saw when using shallow cuts. It is safer to proceed with a series of shallow cuts—providing more control and the opportunity to cool your blade—rather than all-in at once, unless you are pushing a large trolley that can handle depth.

Start the saw at the lowest revolutions per minute (RPM) setting and start your first cut along the guide. Always hold the saw you are using with both hands, and then move the saw tightly against the guide plate and move it forward slowly. Always let the saw do the work; just guide its direction, but don't push it into the concrete. At this point you only need a quarter-inch cut, but if the saw bites a bit deeper, that's okay. The first guided cut will ensure that you keep the cut straight for the rest of the project.

Remove the saw from the concrete and let it spin freely; this provides an opportunity for the saw blade to spit out the dust clogging it and cool it down. Cut alternately for 30 to 45 seconds and cool down for the same time until the project is completed.

After completing the guide cutting, remove the guide plate. Return to a 1/4 inch to 1/2 inch deep cut and continue with an intermittent cut that does not exceed 30 to 45 seconds of running the saw. A nice, shallow, straight line will soon make a 2-inch deep cut in the concrete.

Despite your efforts to keep the concrete moist, dust will still accumulate during the cutting process. Take a break to clear it. Clean it up or use a wet and dry vacuum cleaner to dry it all up.

To make deeper cuts, turn off the saw and use the depth lever or knob to increase the blade depth by ½ inch. After setting the new width according to the technique outlined in steps 7 and 8, continue cutting.

After cutting as deep as possible with the maximum blade depth on the saw, you can switch to a sledgehammer. The hand-push wet saw may have completely cut the concrete; if this is the case, you can skip to step 14.

Clean up the dust in the work area (use a broom and dustpan or wet vacuum cleaner), and put away the saw and power cord. Then, with the protective device still present, hammer the cut concrete. Start near the cutting line, but not on the cutting line, and work outside the cutting area. Keep a distance of one to two inches from all cutting lines and swing the sledgehammer with enough force to break the concrete. When you split the concrete, use a spudger to dig out large pieces and remove them.

Once you have knocked off most of the concrete around the cutting line you made—perhaps you have cut the concrete completely—you can go back and carefully dig out the excess concrete to get a cleaner line. However, if you are pouring new concrete to replace weathered, broken, or cracked driveways or patio slabs, make the edges jagged and protrude an inch or two because it will give the new concrete something to bond.

To get a cleaner edge below the sawing line, you need a claw hammer and a mason chisel. Starting from the bottom of the clean cutting line at one end of the project, align the chisel blade with the concrete, and hit the top of the chisel with a hammer to crack the concrete bit by bit until you clear the rough edges you like.

Move any broken concrete residue to the yard as a filling, sell it or give it to someone else to use it as a filling, or drag it to a landfill for proper disposal.

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