Most trim carpenters don t even use a tape to trim windows.
Tile around window without trim.
Here s how they do it.
Use corner edging tiles similar to countertop v caps but without the raised lip that forms the front edge of the counter.
It s all done by eye with a sharp pencil a miter saw and an 18 gauge nailer.
Set the recess tiles first then the bullnose.
When using a trim choosing tiles which are thin is recommended.
Instead of setting bullnose inside the recess set it on the wall surface.
Ceramic or porcelain tiles are often preferred when using trim as heavier stone varieties often have a greater thickness and are therefore less practical.
The tile will wrap partway up the window and the trim would sit on top of it leaving some of the tile exposed.
To finish the edge of a tiled window you have several additional options.
The tile isn t finished on the edges i m told that very few tiles are as most aren t meant to show the edges.
In addition the tile edging is not expensive it is easy.
For the part up the wall where there isn t tile the trim would have some sort of backing added to increase the depth where it meets the wall.
Whether you tile around a window with a trim or with tiles is very much determined by the materials you use.
Alternatively depending on the style of your room some people finish with a pencil trim or something but that s not always a good solution.
Nonetheless you can still tile around a window using traditional techniques meaning that you just install the tiles in a corner without using a plastic trim it would take longer to get the same neat look.
Use corner edging tiles.
Here s one kitchen where we used some trim around the window the main thing is to not see the edges of cut tile or the thinset there s no magic to the slant of a bullnose.
So a metal trim has had to be added around the wall around the windows to conceal the edges and i m assuming this will have to be done for the storage alcoves that have been built into our shower and boxing around the plumbing.