i fitted a shower in the corner of my bathroom , and built a studded wall as the third side . I placed foil backed plaster boards to the studed wall and then tiled over it , i have had serval leaks from this side as there seems a small amount of movement from tiles and the water get in between the grout , i'm planning to removed the plasterboard from the inside of the studded wall and replace with ply or aqua planels to hopefully give the tiles a better seal . Any ideals which best , ply or Aqua panels ? cheers