Can I build off this?

[padstar]

I am wanting to build approximately 3lm of blockwork on the below existing oversite to form a downstairs WC.

Can I go straight off this without any fear of future issues or do i need to dig and pour deeper?

The concrete is just over 100mm

 

[mattylad]

image has not been posted correctly - its not showing

 

[padstar]

Any etter

 

[Scarlet Pimpernel]

Can I go straight off this without any fear of future issues ..

Not a feline in purgatory chance.

 

[padstar]

Hmm thought you might say that. How deep a footing for a single skin block wall?

 

[Scarlet Pimpernel]

Hmm thought you might say that. How deep a footing for a single skin block wall?

750mm to 1 metre depending on conditions. It could be more.

 

[padstar]

750 - 1000 for an internal single block wall?

If thats the case I may just use timber stud off the joists. Thought you were going to say 400-500

 

[Laggy]

I’ve got an internal block wall in my extension and the inspector said I could just build it off the 130mm concrete slab I poured..

 

[Scarlet Pimpernel]

I’ve got an internal block wall in my extension and the inspector said I could just build it off the 130mm concrete slab I poured..

An internal block wall isn't on the edge of a suspect slab.

 

[padstar]

Sorry the photo I showed was just to demonstrate the depth. That area had been removed for a pad foundation so I thought it would give a good sectional view of the oversite. The wall will sit in the middle of an exiting room tied into 2 other existing walls. Does that make a difference.

 

[Scarlet Pimpernel]

So it's not a double skin load-bearing external wall?
Edit:
Sorry, didn't notice your subsequent explanation.

750 - 1000 for an internal single block wall?

If thats the case I may just use timber stud off the joists.

What joists?

 

[padstar]

It is a single skin blockwork wall, non load bearing to form the wc wall highlighted below in yellow.

Everything below the red dashed line is existing house with an oversite covering within it as in the original photo. The WC will sit right in the middle of the existing ground floor.

All existing joists have been removed and new joists will be installed. I had wanted to build the walls in yellow in blockwork to give a more sturdy construction and had wanted to build them straight off the oversite. Joisst would then be installed throughout the ground floor.

Does that make more sense?

 

[padstar]

So the wall would be built off something like this.