For what kinds of wall structure - tile type combinations a waterproof membrane should be used between walls and tiles?
It's a shower. It needs to be waterproof.
A product I've used and liked is RedGard:
You install your backer board, then 'paint' this on. It's basically an adhesive roll-on rubber membrane. You then tile right on top of it.
I like this better than the traditional plastic-behind-the-backer-board for two reasons 1) You can easily put holes in the plastic during construction (screw holes, for instance) and 2) the RedGard is closer to the 'wet side' of the wall, reducing the chances of water getting into the wall.
As DA01 said Always use wetseal, considering how much it costs it is a worth while investment
- Install the wall sheeting (we usually use villa-board which is a cement fibre board)
- Set the joints on the wall sheeting, fill any gaps between the wall and floor with silicon
- After all the sheets are set and dry
- Apply 1 coat of wetseal, for bathrooms in my state we seal the whole bathroom floor and up the wall 150mm where there is no splash areas and up the wall to a min of 2m in the shower
- Use a fibre wetseal joint tape in all corners eg where the wall and floor meet and where walls meet, this should be install why wetseal is still wet and then wetseal should be re -applied to just the wetseal tape.
- After 24hrs and wetseal is dry reapply another coat over all the area you have already covered
You can also get a professional to do this for you. Having a good wet seal job is very important for the longevity of your bathroom
This YouTube link is pretty good, explaining what can go wrong, as well as how to do it well.