What to do with floor cavity between 2 slabs

[Aps12]

Hi All, any suggestions on how to deal with this floor cavity?

Previously there were some patio doors here which brought up moisture through capillary action via the screws securing the doors to the brick course. Since the removal of these doors there has been no issues with damp/moisture. It’s been dried out for a while now.

How do I cover this section to then lay my flooring? The dpm taped over the flooring isn’t the original and looks to be placed under the flooring underlay. Can I just simple use some self levelling compound. The original slab has some foam insulation between the slab and brick course, it also sits slightly lower by 5-10mm. The new slab has dpm edges butted up against the bricks.

 

[Wayners]

I extended and removed a wall.
There was a cavity across floor.
I dug out 2 courses of bricks.
Vacuumed out.
Lined with plastic
Filled with concrete.

Is that something you can do as similar?

 

[noseall]

Hi All, any suggestions on how to deal with this floor cavity?

As per post above.

You are looking at sub DPC masonry - i.e. damp. Break out a course or two (both leaves), line with polythene, insulation and fill with concrete or screed.

 

[Aps12]

Thanks for your replies, I’m not sure if the other line of bricks is there or possibly buried under the screed. Will have a look again to see if it’s already been removed.

What do I do with the foam insulation next to
The bricks? You can just make it out in the pics as it was screeded over

 

[Wayners]

I didn't bother with foam.
The new side of floor had 50mm of foam under I put down before pouring new slab.
Old side from 60s didn't have any foam.
There was clear plastic under concrete from 60s.