A finishing trowel is a flat plastering tool with a rectangular blade and a handle, used to spread and smooth the top coat of plaster, render or mortar. In Dutch the tool is called a dekspaan. It is one of the plasterer’s core tools and is used for both interior and exterior work.
Shape and types
A finishing trowel has a rectangular blade — typically 20 to 30 cm long and 12 to 14 cm wide — with a wooden or plastic handle. The edges are slightly rounded so material can be spread without leaving lines.
Common variants:
- Stainless steel — the standard for modern plasters; stays smooth
- Galvanised steel — cheaper, suited to rougher surfaces and lime mortar
- Plastic — for pigmented plasters where metal smear would cause discolouration
- Wood (float) — traditional, for lime stucco and base coats
How it is used
The finishing trowel is used together with a hawk (the flat board on which mortar is carried). The plasterer scoops material from the hawk with a small trowel onto the finishing trowel, then sweeps it across the wall or ceiling in long, even strokes. The angle of the blade controls the layer thickness.
Applications
- Interior plastering of walls and ceilings — gypsum, lime or cement plaster
- Exterior render — decorative renders and stone renders
- Levelling layers — smoothing and base coats
- Detail work — corners, window junctions and skirtings
Difference from other plastering tools
- Hawk — the board on which mortar is carried
- Straight edge / darby — used to strike off along a screed bar
- Wide finishing float — larger version for big areas
- Corner trowel — for internal and external corners
Related terms
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