Tiling onto a void space

[VICKI D]

We've recently had a new D shaped shower installed but there is now a void on the outer edge at the bottom where there is no tile. There is nothing behind to apply a tile to. Hopefully the pictures explain this better! How can we fill the gap?
Thanks

 

[J Sid]

I get this quite often, I use thin air adhesive by Ardex

 

[Spare Tool]

There's a bit to grip to, try clear Silicon on back and around the edges of a ready cut tile..

 

[Boggs]

Expanding foam, polyfiller, newspaper, an old sock....

 

[VICKI D]

Wow, thanks all for the quick reply. So many suggestions! I'll get out to the shops and pick up some bits and let you know how it goes! Cutting the tiles is the next battle, but there are a few spares for practice! Thanks again.

 

[Dumbo]

I not being funny but just fill it in with Silicon like the tile next to it