Concrete Power Trowel: 5 FAQs When You Use [Complete Answers]

Concrete power trowel is a construction machine often used on building construction sites. It allows you to achieve a smooth surface of the concrete.

concrete power trowel

A concrete trowel is also sometimes termed a concrete helicopter.

It is made of a rotating blade fixed to the machine at its bottom. Machine powers the blade to rotate it around its axis. When the blade rotates, it straightens down any concrete surface underneath it.

The machine can be either electric or gas-powered. It can either be operated by a worker pushing it on the surface of concrete or riding atop of it to steer it down the concrete surface.

In this article, you will learn about when to use a concrete trowel, how to use it, and what the best practices are.

With a concrete power trowel, you can compress the top layer of the slab. Compressing the concrete will close the natural porous vents or pathways within the existing concrete.

These pathways or vents allow the moisture within the concrete slab to move out and finally evaporate from its surface.

As a result, a smooth surface can be achieved.

In small areas, you can even use hand trowels, but for larger areas, you would need a power trowel.

When Should You Power Trowel Concrete

There is a certain check which determines when you should power trowel the concrete.

A common check is when an operator can stand on the surface of the concrete. While standing, the footprints should be between one eighth to one-fourth of an inch.

The worker should be able to walk firmly on the concrete without sticking concrete on their boots.

When these conditions are met, concrete is ready to be power troweled.

How Long To Let Concrete Set Before Power Trowel

Now you know how to check the state to concrete whether it is ready to be troweled or not. You should also know the exact time when you can start to trowel the concrete.

One big clue in this regard is that you should allow the water on the concrete surface to be disappeared.

Usually, when concrete is poured, you see a shiny surface a top of it. This is usually due to water standing on top of it. When the concrete surface loses this water, it will appear less shiny.

Usually, this can take as less as 20 minutes to even four hours in some cases. It depends on the temperature on the concrete site, humidity, and the intensity of wind:

  • If the temperature is high, the water on the concrete surface would disappear earlier and vice versa in case of cold temperatures.
  • If humidity is high, the water on the concrete surface would disappear earlier and vice versa in case of less humidity or drier climates.
  • If the speed of the wind is fast, the water on the concrete surface would disappear earlier and vice versa in case of slow speed winds or no wind at all.

How to Use It For Finishing Concrete Floor

Concrete floors offer many advantages like:

  • They can be Colored to match any hue
  • They can be finished to look like tile, slate, or marble.
  • They can also be enhanced to achieve various types of stenciled borders and graphics.

For all these finishes, the first step is to obtain a smooth finished surface. This can be done using a concrete trowel.

Best Way to Power Trowel Concrete

Different types of concrete finishes may require a different types of trowels with different types of blades installed underneath them.

In this section, we will show you how to select the right trowel and what is the best way of troweling the concrete.

Choosing the troweling machine

If the area, you are finishing is less than 1000 sq. feet, you can the walk-behind trowel. For larger areas, you may prefer to go for a ride on concrete trowel.

In the case of smaller areas to be finished, it is best to choose blades between 24 and 36 inches.

There could be two types of blades: float and finish blade. In some cases, you may get a hybrid blade, which has the skills of both floats and finishes blades.

When you have to trowel a larger area, we recommend you going got a 36- and 48-inches blade.

However, on corners, you may still have to use a 24-inch blade.

How to choose a proper concrete power trowel

Floating the concrete

While you are floating your concrete, you should use float blades. These blades will allow you to smooth out any bumps, hollow areas, and uneven zones.

It is recommended to run the trowel at three fourth of its speed, while you are floating the concrete and keep the blades flat.

Keeping the blades will also keep the machine from digging into the concrete and ruining all the progress you have made.

Once you have moved the trowel all over the concrete slab once with a flat blade, now it is time to turn the blades.

You must now turn the blades perpendicularly and then go across the entire slab again. This will help you to finish any spots that you have missed in the previous runs.

Finishing the concrete

For finishing, you have to switch to the finish blades. Instead of keeping the blades flat as in the previous case, this time you have to turn them.

Blades should be turned to full pitch and the machine should be run at a full speed.

During finishing, you are finishing and sealing the pore of the concrete. Therefore, you will have to apply the highest pressures to the concrete slab in this case.

You may have to make several passes before you are sure that concrete is finished. You may continue finishing it until the desired look you want, that could be either a glossy one or a mate one.

Lastly, best practices in troweling concrete also involve the proper use of safety equipment. You should be wearing goggles, noise-free headphones, special gloves, and steel-toed boots.

Conclusion

This article was all about best practices to finish concrete with a concrete trowel. Some general checks on concrete are shown to judge, whether it is the right time to trowel the concrete or not.

And lastly, the best practices for troweling concrete that you must follow are explained.