How to fix broken concrete around edges of a bedroom?

[Suzanneizatt]

[MitchellMc]

Welcome to the Bunnings Workshop community @Suzanneizatt. It's terrific to have you join us, and many thanks for your question about repairing concrete.

You image isn't of high enough quality for us to clearly see what's going on there. Could you take another?
 

It appears that you could fill this area with self-levelling cement or patching mortar. If you were to use a self-leveller, you'd need to seal the underside of the wall with gap filler or filler rod so it does not creep out of the area.

Please let me know if you have any questions.

Mitchell
 

[Suzanneizatt]

Tryed the concrete levelling in a bad spot. Has worked but had to wait till concrete had harden a bit as it disappeared under the floor. I made up 5k with 1litre water unfortunately i do not have a mixer for drill and it said not to hand mix but no other choice as i had started so mixed for half an hour. Can i make it a bit thicker instead of waiting?.

[JacobZ]

Hi @Suzanneizatt,

Self-levelling concrete must be mixed to a highly liquid state to allow for the self-levelling aspect of the product to work. I would not suggest mixing the self-levelling concrete outside of the manufacturer's instructions as it will weaken the product and not give you the intended results.

I would suggest purchasing a Trojan 100mm Paint Drill Mixer to speed up the mixing process as it seems like you have a fair bit left to do and this will speed up the process considerably.

As self-levelling concretes are designed to find level in whatever situation they are applied to, if there is no barrier stopping them from exiting under the wall, they will find a way out. I would suggest the addition of the filler rod my colleague @MitchellMc suggested in the rest of the areas that you intend to fill. This will create a physical barrier to contain the levelling compound to the areas you want it to stay in.

Let me know if you require further assistance.

Jacob