Help!: Concerned

[Mozza]

I’ll start from the beginning.. Basically I’ve started to tile the small wall in a tanked shower room, while putting this first section up I pulled a tile to check the coverage which seemed ok around the 75%, the worry I’ve got now is the next day I tapped on the tiles to see if it sounded solid but in random areas of most of the tiles there seemed to be a hollow sound ...
Is this normal or should I be concerned?!?!?!?!
I guess in I'm more worried because it's the first time I've used cement based addy on a wall, the mix did seem ok a good paste not runny not dry..

[whitebeam]

Was it powdered or tubbed gear

[timeless john]

What is the Tanking?

Timeless John.

[peckers]

have you tiled onto a solid wall or is it on a stud wall with plasterboard etc? is it definately the tiles that are hollow? or are you tapping where there is studwork which could sound slightly different to where there isnt a stud.. If its the tiles that are sounding hollow then i would be concerned and further investigation should take place and be re tiled

[davy_G]

What you tiling onto? If its ply or plasterboard it will have a hollow 'knock' as opposed to the solid contact off a block wall. Try popping one off if they aint grouted. If its boast it will come off too easy.

[Fred]

What was the background? Was it sealed? Did you leave the addy on to long?

[doug boardley]

how thick is the adhesive Mozza?

[CJ CERAMICS]

it could be the substrate that you have tiled onto which sounds hollow ie stud wall
if you have spread the adhesive evenly across the wall and twisted the tiles when fitting you should be ok. if possible can you lift off one of the tiles which sound hollow and check.
chris

[Mozza]

The addy was powdered Keraquick the mix was ok I think a good paste not runny not dry..
The tanking was PCI LASTOGUM..
It was only a small section 13 tiles 335x250 on plaster board, most of the walls are board on stud but I believe that section is dot and dab..
I used an 8mm square notch
I think I cover all questions...
Thanks to all

[doug boardley]

everyting seems fine Mozza altho' I've not used that tanking kit myself

[Daz]

It's difficult to be 100% sure, but it sounds okay to me. I'd say that it is your substrate that is giving the hollow sound, unless you think that the substrate was not completely flat and that you haven't achieved an even coverage??

[Mozza]

I've measured the bed behind the tile with a depth gauge, it was 2.5mm and a 8mm notch was used.. I'll still pull one and make sure I think.. If the coverage wasn't at 75% I guess the tiles would fall off the wall when the shower was in use, is that right??

[doug boardley]

if you've firmly pressed and twisted them mozza, I can't see why you wouldn't be achieving decent %age of contact

[Daz]

LOL - I've seen badly fixed tiles that have just a small amount of adhesive in each corner, but they still seem to stay up. The biggest problem will be water getting behind and literally popping the tiles off longer term. You'll also find that the grout will quickly discolour due to moisture behind the tiles, too.

From what you have described, I think you'll be fine!

[Mozza]

Thanks at least I'll sleep better now lol