Removing a floating floor and tiling - first timer

[Nafeun]

Hi guys,

Firstly, can I say that these forums are great!! I am a DIY newbie however being the son of a builder I really do have to give these things a bash.

I live in a 3 bedroom detached house which is about 14 years old. The ground floor is the dreaded “floating” MDF on top of polystyrene. My wife and I decided to tile the dining room, kitchen (inc pantry), utility and downstairs loo in one colour porcelain along with a kitchen refit. I was going to follow the ‘advice’ of a tiler I know and tile directly on top of the MDF using a flex however I came across these forums and im glad I did.

To tackle the job I have purchased 40MM Marmox, Bal primer, Bal SPF, Mapei grout and some reinforced tape along with some power tools.

I have almost finished ripping the flooring out however have some questions.

Please look at the pictures below:

Lovely stuff:



What im left with:


(dining room)


(kitchen - need to rip the rest out of the utility)


(pantry)

One corner I am concerned about is in the dining room, the MDF had cracked and I knew the floor was slightly uneven. This is what I am facing:





Now the second row of blocks have been unevenly laid and has put a lip in the floor as you can see. I am hoping I do not have to use SLC for the base as my wife would kill me and the extra cost.

I am thinking of maybe chipping the protruding problem away with a chisel and thus being nice and flat ready for the marmox? This is the only issue with the floor – the rest is quite even.





What can I place over this expansion gap? – I was going to peg it slightly to give it some support and then lay the marmox over it??


Suggestions are more than welcome J

[whitebeam]

Hi and welcome..

I would'nt chisel the blocks, they are hollow unless it's changed over the years...and could weaken them.

[peteablard]

As above I wouldn't chisel it. What is the height difference? Maybe use 30mm on the higher part??

[Nafeun]

They are at an angle though so 30mm will not work. Could I build it with SPF? I.e a good layer? What's the thickest bal SPF can go? 8mm?

[whitebeam]

Can't you screed the floor..

[Nafeun]

Hmmm how much roughly would
It be for 20 Sqm at no more than 20mm ?

[whitebeam]

Noticed your've already purchased the 40mm marmox boards, so a full 40mm screed would be not viable..