Removing concrete block from basement slab

[dave11]

I'm removing the end of a non-load bearing concrete block wall in my basement. The lowest row is sunk a half-block deep into the basement slab, per the attached pic. Cutting the lowest block flush to the new edge is a challenge, because the concrete saw I used higher up won't cut flush that way. You can see the red line in the pic.

Two questions:

1. Is a masonry blade for a reciprocating saw the way to go in terms of cutting through the lowest block?

2. Should I then jackhammer the lowest half of each block to break it free, prior to pouring new concrete to fill the hole?

Suggestions appreciated.

 

[claydogg84]

1.) Yes, you're going to be looking for some type of diamond grit blade

2.) This depends on what you're planning to do with the floor? I myself would just fill in the void with new concrete.

 

[dave11]

I was wondering though if I'll end up chipping the surrounding slab with the jackhammer, or will the blocks come loose from it once they are broken down?

 

[claydogg84]

I was wondering though if I'll end up chipping the surrounding slab with the jackhammer, or will the blocks come loose from it once they are broken down?

The blocks will break loose inside if you're careful enough. Perhaps a smaller Hilti would be a better option than a jackhammer. What are you doing with the floor after you get the block out?

 

[dave11]

The reason I was going to the jackhammer was because my bosch rotary hammer wasn't making much headway. The blocks are pretty tough.

I was planning to fill the hole with concrete and make it level with the slab.

 

[Jags]

You might be amazed at what a large chisel and 3-5 pound hammer could get done. Those appear to be typical cinder blocks. They don't perform well against blunt force. Simply knock them apart till they are below grade then fill and finish the new surface.

 

[claydogg84]

Unless you're going for a finished/polished concrete floor then there is really no reason to go crazy getting the entire block out. I would knock down an inch or so below the current floor and pour the new concrete on top of whatever is remaining in the hole.

 

[dave11]

Unless you're going for a finished/polished concrete floor then there is really no reason to go crazy getting the entire block out. I would knock down an inch or so below the current floor and pour the new concrete on top of whatever is remaining in the hole.

Got it all done last night. Thanks for the input.