Can i screed over tiles?

[s1oww]

Can i lay a concrete screed over tiles?
I would lay damp proof plastic and insulation over them first, then a thin screed over the top to level the floor.

 

[s1oww]

Anyone?

 

[marshman]

to thin a screed over insulation will break up, you might get away with 50mm of screed with chicken wire in the middle of it.

 

[Monsoon]

What sort of area are you covering?
How deep do you need to go to get it level?

It's worth looking at Tilebacker board.

It's a waterproof cement faced board with an insulation core. Comes in 10mm - 60mm.

You fix it to the floor then prime and screed over the top. If the floor is reasonably level then consider using self levelling compound. You can bulk it up with granite chippings.

 

[s1oww]

The area i need to cover over the tiles is 6m x 2.7m. I'm not sure how deep it needs to be yet as i need to speak to building regs.
At the same time i will be screeding over the main floor in the building, this is 7.3m x 4.5m and need to be about 65mm thick. I'm not sure how i will be getting the thickness yet, it need insulation again for building regs.

Any help would be great.

 

[Monsoon]

The area i need to cover over the tiles is 6m x 2.7m. I'm not sure how deep it needs to be yet as i need to speak to building regs.
At the same time i will be screeding over the main floor in the building, this is 7.3m x 4.5m and need to be about 65mm thick. I'm not sure how i will be getting the thickness yet, it need insulation again for building regs.

Any help would be great.

On my project which was to convert an old building into residential, we were able avoid insulating the floor on the basis of the adverse effect it would have on existing door openings.

If you are screeding over a DPM and insulation then I cant see what difference it will make having tiles or concrete as long as the surface is stable.

As for the 'thin screed'. Why does it need to be thin? The thinner you go the more chance of it failing.

My screed will go down to 20mm in places which is not ideal, although the addition of granite chippings will make a strong mix(so I'm told)