troweling

Troweling is a finishing technique used in masonry, plastering, and concrete work in which a flat-bladed trowel is drawn across a surface to smooth, compact, and shape the material as it cures. The term covers both plaster finishes on walls and ceilings and the finishing of concrete floor slabs. Finishing trowels are typically steel or magnesium, and power trowels may be used for larger areas.

In plastering, troweling follows the application of coats such as scratch, brown, and finish coats. A steel finishing trowel is used to smooth and compact the coating, producing a dense, even surface with minimal trowel marks. Timing is critical: the plaster must have stiffened to a workable plastic state but not yet set hard. Several light passes are common.

For concrete floors, the initial strike-off uses a straightedge to level the surface, followed by floating to bring the mix to a uniform texture. When the surface reaches the proper stiffness, finishing trowels—hand or powered—are applied in broad, overlapping strokes to close the pores and create a smooth, hard finish. Final burnishing with a steel trowel may be done on interior slabs to achieve gloss; overworking can lead to a fragile surface.

Different finishes are produced by changing trowel type, blade angle, and number of passes. Narrow trowels are used for edges and joints; magnesium blades are lighter and less prone to rust. For non-slip floors, troweling may be followed by a textured or broom finish.

Maintenance involves keeping blades clean and dry, sharpening or replacing worn blades, and using the correct pressure and angles to avoid gouging or cracking.