It just creates a better bond to the tile.
Notched trowel for wall tile.
The other main consideration is where the tiles will be set on the floor or on the walls and ceilings.
Mosaic tiles and wall tiles up to about 4 by 4 inches call for a v notch trowel with 3 16 by 1 4 inch notches while larger tiles require a trowel with a square or u shaped notch to obtain proper adhesive coverage.
U notched trowels normally only have one number.
The larger the tile the larger the trowel.
As 1 2 trowel means that both measurements are the same.
Because v notch trowels dispense less mortar than square notch they are also preferred for many wall or ceiling applications.
What size trowel to use for tile tile trowels come in many shapes and sizes generally starting out from a 3 16 v notch up to the 1 2 square notch.
Twelve inch square tiles for instance are best applied using a trowel with 1 2 inch by 1 2 inch notches.
Finding the right trowel for the job is quite simple when you know that generally speaking the trowel size should match up to the tile size the smaller the tile the smaller the trowel.
With your 12 24 tiles you should use a 1 2 notched trowel on the wall and back butter each tile but just with a skim coat.
V notch trowels have a continuous zig zag or sawtooth pattern with points.
When you use a 1 4 x 3 8 square notched trowel you will leave 1 4 wide by 3 8 high ridges of thinset on the substrate with spaces between each ridge.
They are typically used for small tiles such as mosaics or any tiles under 2 inches square.
A tile trowel with only one measurement i e.