Building on a "council" concrete paving slab

[session2]

Hi all,

I'm new to this forum and looking for some advice

I'm preparing an area for a patio. Iv already done half and did a full on concrete foundation but I now need to extend it. I want to avoid the hassle of mixing concrete this time and I have a load of spare 50mm concrete slabs which I want to get rid of and thought i could I use these as a foundation to lay a 1 block high wall which i will then fill with MOT then sand. I guess I'm concerned about the adherence of the mortar as a apose to mixed concrete, but concrete is concrete right? Anyone had any experience of this?

Thanks!

 

[23vc]

What’s the block wall for? How does it relate to the patio? Why are you putting sand down? Pic might help

 

[session2]

The block wall was to establish a shape and contain the MOT I filled it with and I used sand to lay the slabs on. I want to continue to wall to the right. Hopefully the pic helps to visualise.

 

[23vc]

The perimeter blocks should be on a concrete footing and haunched on the outside with the same concrete to stop them moving outwards. I’d avoid just putting them on slabs, as a proper foundation is continuous and prevents sections moving.