can I 'skim' or build out a hollow dip using tile adhesive?

[Tunni]

I'm tiling a 6ft x 8ft plasterboard wall (The plasterboad is dot and dabbed and also dry wall screwed, so it's extremely well fixed) with 400 x 400 x 12mm natural travertine. The wall is fairly plub and level but a straight edge reveals a fairly large central 'hollow dip' of up to 5mm.

Can I true the wall up by using some rapid set floor tile adhesive and running a feather edge board along the surface. I know 5mm isn't much but when I start tiling I'd prefer the wall to be spot on - that way I only have to concentrate on tiling and not struggle with a large variation in the depth of the adhesive.

Hope that makes sense.

Tunni

 

[White Room]

Yes you can, just use a straight edge to make sure it's flat

 

[wetdec]

Yes you can prime it first..... do not skim if your using travertine m8

..

 

[Alan.P]

My question is if dot and dabbed why is there a dip, is it an over tightened screw pulling it in or was it just a bit of over zealous tapping ?

Otherwise, as per the rest

 

[brian c]

serate the wall with adhesive and back butter the tile and this will sort it.

 

[lucius]

Why is it dot and dabbed and screwed? screwed into what.
Lucius.

 

[beanz]

Will 12mm Travertine not be too heavy for Plasterboard?

 

[Tunni]

Having read through dozens of threads I'm told it's a no no to tile onto skimmed plaster. So I dot and dabbed plaster board onto walls and screwed as well into the existing plaster/brick to fix it. (The 5mm dip was due to fixing the last 18inch of PB...I discovered the original skim was out at the edge and even with next to no addy it caused the 'hollow'

Moving on Wetdeck - Can you elaborate, you mean prime as in brush primer or do you mean with addy? And there appears to be disagreement with Whitbeam who says yes I can skim (using addy as explained NOT plaster, just in case you were at crossed purposes)

 

[beanz]

Tunni, you can skim with addy (ideally Rapid Set), but you need to prime 1st with an Acrylic Primer.

I still think you'll be exceeding weight limits though. Plasterboard can only take about 32km/m².

 

[tileform]

Found this link from an earlier topic

Tiles and Adhesive Weight Per Square Metre - THE TILE SOURCE

 

[Olz]

Having read through dozens of threads I'm told it's a no no to tile onto skimmed plaster.

You can tile onto skim plaster, but your
A) wasting time and money skimming the plasterboard as its not neccessary to tile and
B) reducing the amount of weight per m2 from around 32kg/m2 to 20kg/m2.

Id skim flat the void with addy and then tile as others have advised.

 

[doug boardley]

your question is perfectly reasonable tunni, and yes, much better to take the dip out using rapid set addy and a straight/feather edge

 

[redmist6]

You can tile onto skim plaster, but your
A) wasting time and money skimming the plasterboard as its not neccessary to tile and
B) reducing the amount of weight per m2 from around 32kg/m2 to 20kg/m2.

You crack me up..oli..always rely on you for the specific scientific details.....i love it!!

I thought i was the only one!!.....:hurray:

 

[Tunni]

Great info guys, Thanks again for selflessly passing on your hard earned knowledge.

Regarding the tile weight/substrate guides, I appear to be over with 12mm travertine. (Oli why didn't you read my mind ...and let me know earlier!!) Having said that, stats of this nature are usually very conservatively rated. Based on that there must be a fairly healthy reserve....I hope so, as it's one I'll be using! Obviously by paying careful attention to optimise all the other aspects of good tiling practice I should be able to minimise any potential problems.

Tunni

PS. If anyone has any construction/timber/carpentry questions I'd be only too happy to help if I can (I benefited from a family of three generations of skilled carpenters - whilst all my mates were out playing as kids, I'd be helping my dad in his workshop... never bloody forgave him for that!! LOL)

 

[grumpygrouter]

Great info guys, Thanks again for selflessly passing on your hard earned knowledge.

Regarding the tile weight/substrate guides, I appear to be over with 12mm travertine. (Oli why didn't you read my mind ...and let me know earlier!!) Having said that, stats of this nature are usually very conservatively rated. Based on that there must be a fairly healthy reserve....I hope so, as it's one I'll be using! Obviously by paying careful attention to optimise all the other aspects of good tiling practice I should be able to minimise any potential problems.

Tunni

PS. If anyone has any construction/timber/carpentry questions I'd be only too happy to help if I can (I benefited from a family of three generations of skilled carpenters - whilst all my mates were out playing as kids, I'd be helping my dad in his workshop... never bloody forgave him for that!! LOL)

Substrate weight limits are given for a reason. They may or may not be conservative and we, giving advice on these forums, can not recommend that they are ignored. Certainly as a pro tiler, I would not put those tiles onto an inappropriate substrate as a law suit may follow if anything happened. What would REALLY stop me doing so though was the thought of several Kg of tile and wall falling down onto a small child, certainly hurting and possibly killing said child. This to me is an unacceptable possibility and I would not put anyone at risk by doing so.

I assume the tiling is in your own home? If so then you have the right to carry on if you wish. If you do so, good luck and I hope nothing untoward comes of it.