Tiling over exterior tiles

[12yrsintrade]

I never tile over tiles. However, in this case I have a small area that is a shop front and I'm told there is a void behind. I know I could remove the old tiles and assess the substrate, reboarding it if removal of old tiles causes damage, but the existing tiles are sound and I'm tempted to go over them. The customer has asked me to. I'm planning to key in the old tiles with a few notches using a grinder, bal prime it, then rapid set fix some ceramics. Any advice would be appreciated.

 

[Dumbo]

I wouldn't tile over the old tiles ,but that is your shout. If it is only a small area remedial work wouldn't be expensive to do . But if you are set on tiling over I don't know bal prime it, but I would use something like mapei prim grit or the tilemaster grit primer as these are designed for non porous surfaces .

 

[Time's Ran Out]

I don’t think I’d be fixing ceramics to a shop front anyway.

 

[Italy]

if it is solid and covered by rain,
proceed as mentioned above mapei primer grip.
but usually I use mapelastic of mapei outside.
here in Italy it is very common to overlap the tiles.
but it's all solid and no wood underneath. 😉
and when the earthquakes come the houses fall ... 🙁

 

[Time's Ran Out]

@antonio - I doubt if you have the frosts that are here in the UK - freeze/thaw is the threat to ceramic ties.

 

[WetSaw]

@antonio - I doubt if you have the frosts that are here in the UK - freeze/thaw is the threat to ceramic ties.

Oh yes they do, especially in the north where he is.

 

[Huddersfield Tiling]

"I never tile over tiles".
You've just answered your own doubt, and you should stick by it, as you have no idea how good the existing tiles are, unless you smash up a few and look for fractures throughout.

 

[Italy]

"I never tile over tiles".
You've just answered your own doubt, and you should stick by it, as you have no idea how good the existing tiles are, unless you smash up a few and look for fractures throughout.

you can always use a hammer
and listen to the sound of the tiles.

 

[Italy]

@antonio - I doubt if you have the frosts that are here in the UK - freeze/thaw is the threat to ceramic ties.

do you live at the north pole? 🙂

 

[Italy]

in any case I only gave my answer
to the request and specified that it must be solid.
the technical sheets exist to be read.
I know very well how to lay tiles on tiles,
both inside and outside it is 70% of my work.
now I should say a dirty word, but it's Easter and I have to
be good.