Dodgy Screed

[Stewart]

Hi peeps, looking for some opinions on this. I've have a job to tile a 150 metres of travertine on this floor. It's a six week old sand & cement screed on top piped underfloor heating, which in turn is on top of plastic eggbox type insulation on top of a solid concrete floor. The insulation and screed total 70mm with the screed being around 30mm of that.

IMO the floor is an absolute mess and after checking the levels today, it's out as much as 25mm in places. It's also crumbling under foot and crazing in the high traffic area's. I think the screed is too thin and the mix is also too week.

Now I've been asked to quote to level the floor (102 bags) but I believe the screed in going to fail regardless of what I do on top of it. So the questions are.... Can slc over this floor once cleaned and primed, ate there any treatments I can use to sure then a week mix or does the original screed need replaced...??

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[Ajax123]

You need to find out specifically what system was used before Conde ing it totally although on the face of it it does ot look great. The bel tech therm underfloor heating system from schluter conforms to the description you have given. This sytem should be used in conjunction with ditra matting. Schluter are very specific about the details so if it is this system then you should not need to dig p and replace. I am not aware of any other systems like this one although I guess there may be some. In my own opinion if it is not this system run kicking and screaming from it. If it is this system then contact schluter for advice before proceeding but it should be ok to proceed.

 

[Ajax123]

Sorry did not read your full post. Crumblim is usually. Associated with the screed having been laid too dry or drying out too quickly. This would need to be addressed and rectified before tiling could commence. The other issue I see is that levelling it might prove detrimental because a levelling compound might prove too strong to work with the system.

On second thoughts you might be better advising starting again or walk away from it and let someone else have the issues

 

[jay]

If its already craze cracking in heavy walk areas then i would say it is stuffed and might be worth walking away or replace the screed

 

[peteablard]

I'd seriously think about walking away from it. I'd certainly voice your concerns and if they want you to go ahead see if they'll sign a disclaimer.......

 

[hillhead]

30mm depth too, imagine the weight of the trav on top of that and it crumbling too.

 

[White Room]

I would just walk, fast.......

 

[hillhead]

I would just walk, fast.......

Or run,lol

 

[Spud]

I find that Ardex technical are extremely good at giving advice on all types of flooring problems and they have specialist flooring products that lie outside the normal everyday tiling products ,give them a call and they will give you good advice on what to do

 

[Gazzer]

I would be out, someone of your experience is seeing it as dodgy so I reckon you know the answer.

While I understand that various companies will have products that they say will suit this situation I always get the feeling that it will still be a risk. Plus will the client be willing to pay the extra money needed ????

 

[Stewart]

Thanks guy's telling client today to replace screed by reputable company of we leave the job for someone else to make a hash of. This is the third large job I've had to walk away from in the last 2 months due to rubbish screeds totalling over a 1000 metres and it's getting a bit tedious now..... Bring on the ply floors I say...(;0)


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[Ajax123]

Before walking away you should look at the possibilities of repairing it. Ardex have been mentioned. Bostik and flowcrete also do some good stuff. Ardex do psrs which is fornrepairing this sort of thing. No point walking away until all the options are looked at eh?

 

[Stewart]

Have been asked to put concerns regarding this in an email to be forwarded to the screeding company. Though my concerns are based as a tiler and not an expert in screeds and we'll see what happens. This is a pic of the little shack that has the problems....

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