Cinderblock repair help needed

[Danaus29]

In tearing off the addition on our fixer-upper we found a couple blocks (cinder block construction on exterior walls) that had pieces busted out of them. I think they are 3 hole blocks and one whole side of one hole is busted off on one, and most of one hole on another. No telling what we will find as we finish taking off the rest of the addition. Anyway, how would you go about fixing the broken pieces? Put wire mesh (hardware cloth) behind the holes and patch with concrete mix or mortar in a small piece of concrete from another (new) block??? And what to do about the chunks broken out from pulling the nails from the framing that was attached to the block? Would mortar mix be an appropriate repair or should I do something else? Thanks for any help. BTW, any good books about concrete/cinder block repair? Preferrably one with step by step instructions.

On the upside we now have the bathroom window cleared and opened. Now I just have to get the window removed and get the glass block co out for an estimate. DD and I have done pretty good at getting this project started. She is a hard worker when she wants to be. Dh is impressed with the progress we have made so far.

[Toads tool]

If I was going to try and repair it in place I would pack the whole void with something and cover with a patch of hydraulic cement. I'm thinking expandy foam so you can trim it.
The little missing chunks, I would fill with something like Durham rock putty.
I would replace the busted blocks if it were my own. Then I could butter up a new one using standard mortar. Trying to find a matching block is another story, they vary enough to make a replacement, look like a replacement.
None of these fixes are going to be pretty. So you may need to paint if seen from outside.

[Rocky Fields]

Hey.

Technically, the damaged block should be cut out with a masonry grinder/hammer & chisel and then replacements should be relayed with the appropriate mortar mix.

RF

[stranger]

pack it right full of concrete, trowel it smooth and forget it, if it's holding the way it is, the concrete will just make it stronger and look better.jmo
actually you have the right idea about how to repair it

[tiogacounty]

I have done this several times while doing electrical work in schools and commercial buildings. Basically, it's a matter of refacing the damaged block with a new slab. Using a brick chisel and a small sledge, remove the face of the old block and surrounding mortar to a depth of 2" or so. Now cut the face off of a new block. A 4" angle grinder with a diamond blade works great, but careful chiseling will do it also. Next, you butter the sides of the slab with mortar and fit it into place. The trick here is to use little shims like small pebbles or 1/2" galvanized nuts to support and position the slab until it sets up. After it sets up, remove the shims and touch up the mortar joints. If the wall gets painted, the patch is invisible. For small chinks and other damage, hydrylic cement is really easy to use and works great. Good luck.

[Danaus29]

Thanks all. I don't think the blocks can be matched up with new ones for replacement. The structure is from the 50's and I doubt we could find blocks the same size. We'll have to check though, one block is really bad. The previous owner broke out 2 of the 3 sections to run electrical wire through. The exterior walls will will eventually be repainted or sided. This is on the back of the house so looks won't be as important.