Floor leveling.

[tiler tom]

Doing a clients kitchen walls. The floor has already been tiled with slate. The client is far from happy with the end result as it is all over the place and out of level in all directions. I know it is the intention to rip the floor up and start over as it is a total disgrace. There is the chance that I will be offered the job of re tiling. It seems that the original substrate was terracotta tiles with an unknown surface underneath. The original tiler threw down patches of self levelling in the low points in order to try and level without success.

How would you go about levelling the exposed terracotta to a standard to tile. The floor area is approx 4sq and dips 20mm in some corners.

 

[grumpygrouter]

Sticking my neck out a bit here Tom and it is absolutly possible that I don't know what I am talking about, but... do you know if the slate had been graded, and if so, has the "thinner" bits been put around the edges/corners? This MAY account for the differing levels. If you are sure the current tiles are "flat" and it is definately the previous floor that is wrong then I am not sure what you would do re leveling terracotta. I know teraccotta isn't the easiest stuff to work with as it absorbs a huge amount of impregnator to seal it. If they are sealed it may have needed stripping away before any attempt to level it. I don't have specific terracotta details in either my Ardex or BAL "bibles, but maybe you can treat them like normal "unglazed" tiles.

Hopefully, Dave Gaz or Pete may come online later and give better advice. I will be watching with interest.

 

[GazTech]

Given the chance I would have taken the cotta tiles up, and gone back to basics.I would strongly recommend to your customer you start afresh. Thick cotta followed by slate, at least remove a corner section and check out the integrity of the floor before making any moves, I'm sure your customer will respect your professionalism, so let us know what happens.....Gaz

 

[tiler tom]

Thanks guys for your replies. I can only tell you what I have been told myself by the customer as the slate is already down.
The house is a 1900 ish terrace so although everything is solid the floor and walls are all over the place.
How the floor was described to me was that underneath the lino there were terracotta tiles these i was told were quite thick. I got the impression that they were terracotta colour and an old tile. I asked him why he didn't take them up first but he was unsure what was underneath and didn't want to create more problems so it was decided to go on top of the tiles.
With reference to grumpys post the floor was not out of level because of grading it is high in the centre and falls away towards the corners and doorway by as much as 20mm over a metre to one corner in particular.
The customer is going to get the floor up himself but the floor then needs levelling over the entire 4 metre area. The new kitchen is already in so it is a central area.
I have to go back on thursday to finish of the main wall as a plasterer needs to level. I will take pics if I can as you wouldn't beleive how shoddy the job is. He didn't even use impregnator so the grout is imbedded in the tile ridges !

 

[GazTech]

Thanks guys for your replies. I can only tell you what I have been told myself by the customer as the slate is already down.
The house is a 1900 ish terrace so although everything is solid the floor and walls are all over the place.
How the floor was described to me was that underneath the lino there were terracotta tiles these i was told were quite thick. I got the impression that they were terracotta colour and an old tile. I asked him why he didn't take them up first but he was unsure what was underneath and didn't want to create more problems so it was decided to go on top of the tiles.
With reference to grumpys post the floor was not out of level because of grading it is high in the centre and falls away towards the corners and doorway by as much as 20mm over a metre to one corner in particular.
The customer is going to get the floor up himself but the floor then needs levelling over the entire 4 metre area. The new kitchen is already in so it is a central area.
I have to go back on thursday to finish of the main wall as a plasterer needs to level. I will take pics if I can as you wouldn't beleive how shoddy the job is. He didn't even use impregnator so the grout is imbedded in the tile ridges !

A Victorian house like that, you will maybe find that the cotta is in fact encaustic quarry tiles...if they are firmly fixed.ie the floor hasnt moved and loosened any, washed down with sugar soap, primed with acrylic primer, and screed with SLC. This will give you your perfect starting point for new tiles.....Gaz

 

[guy1976]

if your worried about slc sticking to existing terracotta i would use a latex slc such as arditex or mapei latex plan the mapei is the easiest to use and also doesnt smell like urine

 

[wivers]

I wouldn't recomend arditex as it self levelling properties are absolute awful !!

Ywice i have levelled a floor with thats stuff and twice t has sat in the middle of the bloody floor like a huge lump of cammel dung!

Yea yea i know move it around with a trowel.... rubbish !!

SLC is nowhere near as easy to use as people say it is. I know i aint the smartest but if it was that easy to use even i would have no problems wiv it.... but i do ... i hate it..... if it were a holiday resort it would be Bogna, if it were a car it would be a 1980's granada and if it were a person it would be a 90 year old grandad in a caring home because as Guy says it stinks of wee

Anyone how says using SLC doesn't take any skill and is a peice of cake to do is either very very clever at it or talks utter ****e coz for the simple ones amongst us (i.e me) it is the curse of the devil!!!!!


Rant over go back to your homes, "nothing to see here, move on please"

 

[tiler tom]

Surely the best was to lay SLC is to get it down smooth with trowel and tamp.

 

[GazTech]

Surely the best was to lay SLC is to get it down smooth with trowel and tamp.

Yes tom, but wivers is talking about latex compound...much more skill involved in that type it requires much more manipulation than standard water based.....Gaz

 

[DHTiling]

If the original tiles are quarry tiles etc..they would probably have been fixed on a sand cement bed and butt jointed ...not allowing for any movement in the substrate...this can cause the tiles to heave and settle with thermal movement etc...If they are solid and no hollow sounding to them .. then i would use an uncoupling membrane ( Ditra is my choice..)...and there will lots of joints to tile over with them being small tiles so ditra will also act as a crack isolator...
This is just surmising that they are quarry's....either way its worth checking before re-tiling.....good luck.........