Darciegage2 has the best solution.
Large gap between tile and wall.
Large gap between tub and tile 1 2 how to caulk.
Get photos of great finish details include photos with bid and contract.
If your gap is smaller than 1 8 inch in width use regular caulk.
Push the appropriate size backer rod into the gap below flush with the surface.
Any gap should never be greater than 1 8 inch.
Never fill this gap with grout because tile grout is not flexible.
Fill larger gaps with foam backer rod sometimes called spline.
A pencil tile trim would cover the gap.
Thread tools search this thread 1 01 27 16 09 51 am b.
The gap is easily filled with the tile wall grout.
Caulking is the best choice for this application.
If you have tile on the wall adjoining the tub select a caulk that matches the color of the grout.
This small gap is created by the compressed thickness of the organic mastic or the cement thinset used to attach the tile to the backer board.
This can be found at well stocked hardware stores but not always at large home improvement centers.
Backer rod and caulking masking tape off the wall and tub to pull a straight line.
Big box stores have them.
The tile council of north america recommends at least a quarter inch gap between the tile floor and the walls.
Fill gaps larger than 1 8 inch.
Caulk normally used would not work because it s too large a gap.
Ceramic tile wall gap back of tile should rest on finished wall.