Curious question on foundation/fill method

[asnoop20]

Putting in a garage step and it's allowed me to see the concrete fill. Having no experience with foundations I'm curious:

a) what the process is here, does the inner get filled with rubble/dirt level to the blocks, sheet down, wood of height equal to two bricks placed on the outer bricks and secured to give the cavity, concrete poured, set, remove wood, continue building layers up?

b) whether the plastic sheet that's been used is the waterproof barrier for the inner masonry?

The concrete fill measures roughly 120mm deep. The distance between block and brick is 55mm.

 

[noseall]

Putting in a garage step and it's allowed me to see the concrete fill. Having no experience with foundations I'm curious:

a) what the process is here, does the inner get filled with rubble/dirt level to the blocks, sheet down, wood of height equal to two bricks placed on the outer bricks and secured to give the cavity, concrete poured, set, remove wood, continue building layers up?

b) whether the plastic sheet that's been used is the waterproof barrier for the inner masonry?

The concrete fill measures roughly 120mm deep. The distance between block and brick is 55mm.

View attachment 396422

Build up brickwork.
Fill with clean hard core and compact, up to suitable level.
Sand blind.
Compact again.
Lay polythene and drape it up and over bricks.
Fill with concrete and trowel the surface.

 

[asnoop20]

And the cavity would be filled with wood up to the level of the brick, then later removed?

I may have it wrong but the inner masonry doesn't look like concrete block. That would make more sense though to lay an inner course and fill that with concrete rather then faffing with wood. Guessing!

 

[noseall]

And the cavity would be filled with wood up to the level of the brick, then later removed?

I may have it wrong but the inner masonry doesn't look like concrete block. That would make more sense though to lay an inner course and fill that with concrete rather then faffing with wood. Guessing!

A garage opening would not have masonry across it at all. A regular masonry opening (full height door opening) in say a house would not have internal masonry at all, just the outer course. The flooring concrete would carry on up to the sill.

 

[asnoop20]

I've added the door which is why it's a cavity wall.