Floor screed

[Leader]

Hi Guys
Hoping some of you can give me some advice on a job i have booked in for kitchen floor tiling.
The customer floor has had a self leveling compound (Mapei Restoration)laid down over the top of bitumen. Few concerns i have is that on part of the floor a hole has appeared around 100mm in diameter also the guy who laid it had come back on the customer request to redo some it as it wasnt level down one end of the kitchen.
Now the guy has over mixed it as you can see in the photos their was air bubbles in the mix also cracks have appeared.
Their is no UFH under the screed the screed i was told has been down for 6 weeks , other than the hole that appeared the rest of the floor does seem pretty solid. I was already going to put down decoupling membrane ie BAL or Ditra but i dont want to fix this down if the screed is not good enough and possibly needs redoing. Thanks

 

[Leader]

Hi Guys
Hoping some of you can give me some advice on a job i have booked in for kitchen floor tiling.
The customer floor has had a self leveling compound (Mapei Restoration)laid down over the top of bitumen. Few concerns i have is that on part of the floor a hole has appeared around 100mm in diameter also the guy who laid it had come back on the customer request to redo some it as it wasnt level down one end of the kitchen.
Now the guy has over mixed it as you can see in the photos their was air bubbles in the mix also cracks have appeared.
Their is no UFH under the screed the screed i was told has been down for 6 weeks , other than the hole that appeared the rest of the floor does seem pretty solid. I was already going to put down decoupling membrane ie BAL or Ditra but i dont want to fix this down if the screed is not good enough and possibly needs redoing. Thanks
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I forgot to say the tiles that are eventually going to be fitted are 600x600 porcelain 12mm

 

[Spare Tool]

Afraid you already suspect the answer...great product Mapei reno screed but used badly!! I wouldn't fix anything on that, do you know if it's even been primed correctly?

 

[Leader]

Afraid you already suspect the answer...great product Mapei reno screed but used badly!! I wouldn't fix anything on that, do you know if it's even been primed correctly?

Hi Andy thanks for the fast response i will be honest the customer doesnt know but based on what i have seen i wouldnt want to assume he has.

 

[Leader]

I was thinking to take it all up and redo it myself and use the Arditex NA as i believe you dont need to prime it.

 

[Dumbo]

Arditex na is a great product . You will do no harm in priming and it will actually stop the substrate absorbing moisture so keeping it live for longer to help with the levelling .

 

[Flintstone]

Take it up! Looks like it's not bonded.

 

[hmtiling]

If Mapei eco prim wasn't used first, wh8ch I doubt it was, then it's wrong. A mechanical grip primer, slurry coat then leveller or Ardex na

 

[Leader]

Thanks guys for all your responses and help i will let the customer know what needs to be done.

 

[Dumbo]

Sorry i missed the bitumen bit, yes mapei ecoprim grip should be used prior to levelling

 

[Leader]

Just a few questions Is the tilemaster prime+grip ok to use as a primer , should i treat the Arditex or Mapei self leveler the same as anhydrite ie when set remove laitance and should i still use ditra or Bal matting on top of the screed once set even though their is no UFH.
Thanks

 

[LM]

Just a few questions Is the tilemaster prime+grip ok to use as a primer , should i treat the Arditex or Mapei self leveler the same as anhydrite ie when set remove laitance and should i still use ditra or Bal matting on top of the screed once set even though their is no UFH.
Thanks

That primer will be fine once you’ve removed the failed levelling compound completely. If laid correctly Renovation screed does not need any further work to tile to. With a porcelain tile you won’t need to decouple although it’s never a ‘bad’ thing to do with tiles this size, but unnecessary in this case.

 

[LM]

Just to be sure what are the dimensions of the room in relation to expansion?

 

[Leader]

Hi Lee
Width 2.5m length just over 7m

 

[LM]

Hi Lee
Width 2.5m length just over 7m

No need for one then.

 

[Leader]

That primer will be fine once you’ve removed the failed levelling compound completely. If laid correctly Renovation screed does not need any further work to tile to. With a porcelain tile you won’t need to decouple although it’s never a ‘bad’ thing to do with tiles this size, but unnecessary in this case.
[/QUOT

No need for one then.

No need for one then.

Cheers for the help Lee i tend to always put a expansion gap in if its over 5sq meters or more in each direction. I dont tend to do really big flooring jobs as i have been working for less than18mths as a tiler and still learning i mainly concentrate on smaller jobs until im 110% confident i can carry out the work to a high standard plus i dont have the speed of others as i like to make sure its correct.