Large gap between bath and walls

[Kitsune]

We have a new ensuite and it's ended up being slightly longer than expected for the bath. We are left with a gap of between 10mm to 15mm where the bath meets the wall on both short edges. On the tap side it's about 10mm from the wall on the front increasing to 15mm in the corner. The other side is opposite with around 10mm gap in corner and nearly 15mm at the front edge. The bath is all fixed and battened in place.

Not sure whats the best solution for tiling that minimises risks of leaks and looks good. There will be a shower over the bath.

Tiles are 600 x 300mm and 8mm or 10mm thick, not decided which ones yet.

First tiler would fill the gap with expanding foam and thinks we will lose the gap with the tiles and adhesive. I worry the corner will get a lot of water from showering and it's got the widest gap.

Second tiler recommended moving the bath closer to the shower wall and then sliding a tile down the other end. As the bath is all fixed and battened in place could it end up being a bit of a pain. Moving the bath would leave a bigger gap the other end possibly up to 20mm.

Which seems best solution?

 

[CountryFan]

I’m not sure expanding foam is the way to go. Maybe fill the gaps with silicone sealant if possible and maybe use quadrant tiles?

 

[foxhole]

Stick some cement board either end reducing the gap before tiling.
(It will also allow you to square up the ends)
Looks like PPP.

 

[Kitsune]

Stick some cement board either end reducing the gap before tiling.
(It will also allow you to square up the ends)
Looks like PPP.

Thanks, we spoke to one of the tilers about building out the wall but they said it won't look great. Can you get tile trims that cover the 12mm cement board, 10mm tile and few mm for adhesive?

I can kind of guess but what is PPP? The builders were trying to avoid the room being too tight and having to cut the bath in but it's ended up going the other way!