Screed / self levelling compound help

[JonHeath]

Hi all,

I'm in the middle of an extension. I'm opening up a kitchen diner space as well extending it. This leaves me with multiple floor levels with internal walls grounded. Part of this is made up of quarry tile, part made up of solid concrete, and part made up of existing screed.

I'm bringing it level with an adjacent wooden floor. Some places just need bringing up 10mm or so but others as much as 50mm. The area that needs bringing up is about 18sqm.

It feels like any traditional screed options are off the table as the depth isn't enough? I also don't want massive drying times of waiting over a week before laying the floor.

So am I just left with buying lots of Self Levelling compound that can handle up to 50mm depth? Or are there any other products out there. Recommendations of self levelling compound very welcome as there seems to be lots of choice.

Cheers
Jon

 

[^woody^]

Take the tiles up and break the screed, level the concrete?

 

[JonHeath]

That is an option. So basically you're saying, bring the concrete level up? That's not something I'd considered as I'd assumed it would be liable to cracking, same as a thin screed?

If I remove the tiled area including screed then I'll be left with about 50-60mm depth to fill in about half the 18 sqm area. The other half is just concrete (no screed). This needs bringing up about 20mm on average. Presumably too thin for a concrete layer?

 

[^woody^]

That should have been "self level" the concrete - ie make the areas deeper where possible to accommodate screed, leaving just the areas of concrete to self level.

In practice screed can go down to about 30mm thick, if there is a good key, a good mix and fibres used to control shrinkage.

I've had success with rendering sand, in small areas of 15-30mm deep.

 

[JonHeath]

So basically where there's screed, rip it up and relay it so I need less self levelling compound at the end? I had thought about doing that (it would certainly save £££ on levelling compound). My main concern though is drying time for screed. How long would you recommend? I've read some long drying times. I want to lay Karndean at the end of this...

 

[^woody^]

You could use some driers/dehumidifiers to accelerate the drying. You might be better off asking that question in the flooring section.