The family own a holiday chalet in France. I decided to construct an outside shower (it's sheer bliss having a shower in the sunshine! - and the neighbours do stare so!). I laid two layers of concrete blocks, filled the hole with rubble then sand, steel reinforcing grid and about
2" of concrete. The top was finished off with a cement layer and before it dried, I plonked down a layer of tiles - 16 x 300mm x 300mm.Now, after two years, all the tiles sound hollow when they are tapped, and if pressed down some brackish water can be squeezed out :-( It would seem that they are all only held in place by the tiles around the perimeter. The cement has stuck just at the outside edges of the tiles and the sides of the base.
Now, I was going to bite the bullet and take them all up and relay them with a thin smear of adhesive. The problem is that if it is too thick, the drain will lie too low below the tile surface.
I have been given two ideas of how this repair may be carried out:
#1 Take off each tile one at a time, paint the concrete surface and the underneath of the tile with thick gloss paint, and replace.
#2 Drill a small hole in the grout where the four corners of each tile meet, and using a home-made funnel with a thin enough spout, pour in thinned Unibond glue. The capillary action would then spread the glue around.
I have been assured that both of these methods were almost guaranteed to produce really excellent results.
Can I believe this - or is there yet another, better way? The problem with #1, is that it is only necessary to get a small piece of grit underneath and the gap becomes too large and/or the tile will rock. #2 has the problem that would the capillary action be good enough to provide a good 'stick'.