I have opened up some holes in the concrete block walls during my electrical and plumbing projects, most of them the size slightly larger than electrical boxes but some bigger.
I have decided that for the holes that are above the slab, I will use those foamy GREAT STUFF products to just fill the gaps.
For holes that are on the wall but below the slab (my floor slab is about 24" above grade) whether it may be above grade or below grade, I will fill with some slurry mix or sand topping mix. The question I have is how do I do this?
If I have a rough hole about 4"x4" in the block wall, a 3" pipe runs through it, now I have narrow space of 1/2" more or less around the edge of the pipe. How so I push or pack those mix in? Do I mix it dry and push it in as much as I can with a stick? Does not think this will create any uniform patch. Or do I mix it very wet and put it in some sort of a cone with a small nozzle and try to force it into the hole, sort of like how pastry chefs put cream in a paper cone and squeeze them out to make patterns?
Thanks in advance,
MC