When buying a power trowel, the foremost factor is how much area are you trying to cover. Finishers measure performance in square feet per day. A typical big box store has a slab of 120,000 square feet, and an average house slab measures about 2000 square feet. If you finish 6000 square feet per day or less, then you could get by fairly easily using walk-behind power trowels, says Tom Leyes, from Allen Engineering.
Once you've settled on a walk-behind, you still have several choices to make. Walk-behinds come in three main sizes based on the diameter of the trowel blades: 30, 36, and 46 inches. They feature gas-powered engines, ranging from 5 to 13 hp.
The machines, like their ride-on counterparts, use three main types of troweling attachments. The finishing blade is a 6-inch wide blade that is typically used for the final pass. A combo blade is 8 inches wide, and employed during the middle stages of the process. The third type is the float pan, which fits over the blades.
Float pans have really changed the way finishers trowel floors, Leyes says. Introduced in the early 1990s, they have several advantages over traditional blades. Pans can increase productivity and are better able to break open the concrete surface. While in the field, the use of pans over blades is a matter of preference, Leyes says, however, pans do tend to produce flatter floors.
Walk-behind power trowels have several important benefits. They are easy to operate. An inexperienced finisher can handle a machine with little training. The machines are easy to maneuver on the slab, particularly around floor penetrations.
But most important, walk-behinds are well suited for edge work. In fact, walk-behinds commonly are used along the edges of larger slabs, while ride-on machines work the interior. The walk-behind's only significant drawback is the need to trowel over footprints.
Capitalizing on one of the walk-behind's many benefits, some manufacturers have begun making lighter, more maneuverable machines. Lightweight machines—weighing as little 24 pounds—are easier to carry and haul around, and allow finishers to begin working the slab sooner.
As an alternative to walk-behinds, finishers now have the option to buy radio-controlled machines. Chris Corbitt, president of Tibroc Inc., which makes the Tibroc radio-controlled power trowel, says “We are focusing our effort on the residential slab environment; 85% of residential slabs are still finished without power trowels of any kind.”
Its advantages, according to Corbitt, are that you don't have to walk on the concrete with a remote controlled trowel. It is more mobile than a walk-behind machine. It covers an area faster—up to 1000 square feet per hour—and quickly moves from one end of the slab to the other. Its size—40x22 inches—simplifies working around plumbing and edges.
The cost is a little more than an expensive walk-behind trowel and does take time to learn, but it weighs only 90 pounds—light enough for one person to carry.
For more information contact Tibroc at 619-309-5015 or www.tibroc.com.
Here is a selection of other walk-behind power trowels on the market now: