Builders!!!! - Tile Advice

[wayne]

just been to look at a job where the builder had bought some sandstone 3 inch thick,8 inch tall and 40 inch long. They were still damp and he asked me to stick them above a ground floor window as a feature. The wall was painted render and it was raining as well. He said just knock some rapid set up stick them on and I will get the joiner to prop them up for a bit I could hardly hold them above my head and when I refused to fit them he asked me to leave some rapid set and he will sort it. Anyone know if there's a weight limit for adhesive or a shear strength. I told him they needed chopping in and mechanically fixing but he wouldn't listen.

 

[widler]

Id chop the render off down to brick, score the back of the stone , sbr it and stick on with either s/c or addy, then render around it when its set

 

[StevieBoy]

I think if it were me, I'd pass on this one.
Sounds like a right headache.

 

[White Room]

I want to be using some mechanical fixing as well.....

 

[SJPurdy]

Yes there are weight limits for adhesives and the shear strengths will have been measured but you probably need to ask the manufacturer what they are. There are also maximum tile sizes for each type of tile/fixing technique which only some manufacturers manage to put in their data sheets.

This "builder" needs to get a more experienced builder (or architect) in to tell him how to do it properly/safely rather than a tiler to blame if it all falls on someone's head!

My guess is it requires supporting from underneath (RSJ?) and mechanical fixings in addition to sand/cem or adhesive fixing but it is not the type of work I would have wanted (too heavy for me I suspect) even with a written spec how to do it.

 

[widler]

If its stuck on right, rendered around it won't need screwing on .
It may just be me but ive seen tiles , stone and the like 'stuck' on high rise flats, offices ect .
Done right it aint going anywhere

 

[Old Mod]

You're relying on some plasterers rendering!
I'd wanna Chemfix two metal studs in them!

 

[StevieBoy]

Nah, just duct tape them

 

[widler]

nope, im relying on the skill of a trsdesman .
Are you 5 or 6 saying all these buildings around the world,with stone cladding and such like are just held together by luck ???
cos they aint held by metal studding or screws, they are held by render and such like .obviohsly the architects and design engineers are wrong, and you 5 or 6 are right

 

[wayne]

I left it up to him to do what he wants with it. Not having one of them falling off on my conscience

 

[widler]

They fall off, it aint been done right .
Ok, im off , catch u all later

 

[SJPurdy]

Where tiles are fitted externally to high rise walls they can be stuck on with solid bed of adhesive to a good quality render coating that is itself usually coated over a mechanically fixed mesh. Again this is something that I have no direct experience of other than the general adhesive manufact's blurb (and it may be out of date with regard to current specs).

The original post is not about tiles though it is 75mm thick stone (200mm high x 1m long) and I still do not think it is something that is appropriate to stick onto a render surface (even if paint removed) without some permanent support - i'm guessing it must weigh about 45kg. Therefore I'd still not risk putting it up without an expert opinion/specification so I think Wayne was wise not to do it.

 

[Old Mod]

If its stuck on right, rendered around it won't need screwing on .
It may just be me but ive seen tiles , stone and the like 'stuck' on high rise flats, offices ect .
Done right it aint going anywhere

Yes if a whole facade is done! Cos it's gonna have support from the bottom up!
But ur talking about having 2 thirds of it hanging out the wall, and that's if its chopped into the render first!