Garage floor self levelling help

[Silver Birch]

Hi guys I have a 30 sqm garage floor I want to tile. The concrete slab was laid in 3 sections and is dipping towards the centre by about 10mm. Not used self levelling compound before so wanted some advice, can I add sand to compound to make it go further? How much compound would I require for this area? SBR concrete surface prior?
Thanks in advance

 

[One Day]

Is there a DPM under the slab?
At 10mm nearly all slc will not require bulking out.

The issue of damp (or not) will really dictate what you need to use here...

 

[Silver Birch]

Dpm under concrete base done about 3 years ago, dry surface

 

[One Day]

I'd suggest BAL LevelMax or TileMaster's RapidLevel 30.
As the slab is sectioned, you should either include expansion joints or use an uncoupling layer.

 

[Bill]

Get a fibre reinforced SLC for added strength. I like the Tilemaster SLC range and you would probably need 8 - 10 bags if you are skillful at using an SLC.

It all depends on how many hollows and bumps are on the concrete to know exactly how many bags.

 

[GoneGuy]

As @impish said in his post, make sure you prime the concrete floor first with either slc manufacturers recommended primer or use sbr and depending on the porosity of the concrete you might need two coats of primer.

 

[Flintstone]

Don’t be tempted to add sand to the slc, it will mess with the makeup of it. I’ve seen one where sand was added and it just held moisture and didn’t set hard

 

[Silver Birch]

Thank you for your replies gents much appreciated