new footing on top of existing slab/footing

[Jmeng1026]

See the attached sketch. My client is removing the existing foundation wall and pouring a new wall. The contractor just proposed keeping the existing footing and slab and installing some compacted stone to match the top of slab height and then pouring a new footing on top of that.

Do you see any issues with this?

I have never seen it done but have also never been asked about it.

If it look acceptable should they install an 14" #4 bar vertically (4" into existing footing, 4" through slab and 6" into new footing)

 

[civeng80]

I had something like this a few years ago and poured concrete directly over old concrete footing.

Why not pour the footing directly on the existing footing and do away with the compacted stone.

 

[Greenalleycat]

I don't like it.
As Civeng said, ditch the stone and pour that bit in concrete
You'll get a much better connection and reduce risk of weird stuff happening with the hardfill