Tiling Onto Uneven Concrete/bitumen Floor

[Markhi43]

Problem:

• Tiling a kitchen floor.
• Half is covered in bitumen (from parquet floor). Half is a new concrete slab.
• There is a 35mm level difference across the floor and is fairly lumpy.

Possible solution No.1?:

• Use latex self-levelling compound such as arditex na.
• BUT: I am slightly worried the new slab may move and crack along the joint. Which will crack the slc and the tiles.
• BUT: This solution will offer no insulation and due to the level difference will cost an arm and a leg!

Possible solution No.2?:

• Lay chipboard tounge and groove flooring. Using an adhesive to take make it level (in a similar fashion to dot and dabbing) then tiling onto that. Maybe screwing it to floor as well
• BUT: will this stand the test of time?
• BUT: is there an adhesive available to do this?

Please, please help. Gone round and round in circles with this one. Thank you in advance

 

[Old Mod]

Hi and welcome to the forum Mark!
Yep problems.
Firstly I spose, who are u to this job?
You're own home?
Are u a tiler?
Builder?
Diyer?
Oh option two! Nah! Haha
This is why we ask new members to post here first, to tell us a bit about yourself so that we can help u best way we can.

Welcome Forum | New Members Say Hi Here

It's difficult to assertain what level of advice to give otherwise.

 

[Markhi43]

I own the house yea. I am a DIYer, but have a fair bit of experience now. The house has been a big refurb project. Every single room has needed replastering/rewiring/re-everything.

 

[Markhi43]

Thanks for your response. Hopefully I can offer some help to others once I'm through with this job

 

[Old Mod]

Just on the information given,
In broad terms, u could grind off high spots in the concrete, and grind off the bitumen, then use a lot less leveller and try putting a joint in the tiles directly over the join in the sub floor.
But that's broadly speaking, without knowing what levels u need to work to and so on.

 

[Markhi43]

Any idea how we get the bitumen off? Thanks again

 

[Old Mod]

Yeah it'll grind off along with your high points, and if there's any left once that's done, it can be treated with a slurry coat, then tiled or slc'd.
But to remove as much as possible first, is a better solution.
U can hire heavy duty floor grinding equipement.

 

[Markhi43]

Is that an sbr/cement mix. Will this adhere to bitumen?

 

[Qwerty]

Is that an sbr/cement mix. Will this adhere to bitumen?

Yes it is & yes it will......like the proverbial to a blanket!

 

[Markhi43]

Tidy! So could I just put a slurry coat on then use standard self levelling compound on top?

 

[Qwerty]

Best removing as much as possible as already advised, then the SBR slurry, followed by a SLC over this.

 

[Markhi43]

Alright. Thank you for your advice. I'll talk it through with the other half . Her folks are insistent on the chipboard sub-floor.

 

[Ian]

Alright. Thank you for your advice. I'll talk it through with the other half . Her folks are insistent on the chipboard sub-floor.

Do not turn a concrete substrate into a wooden one, that is not a good piece of advice. Clean the bitumen up and level the floor. Even if you were to put chipboard down (which you shouldn't even consider), you'd still need to put a backer board over it to make it tileable, all those layers would leave you with a 40mm step into the room.

 

[CJ]

Also, don't forget a expansion strip between different areas.

 

[Markhi43]

Okay. Not too sure where that goes but I'll work it out. Thank you all.