What is the possibility of putting a new 4″ thick slab of concrete over one that’s 30 years old? It is very cracked but seems to be stable as far as settling goes. What are the pros and cons of this rather than jack-hammering out all of the old.
george fisher
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The old concrete cracked for a reason. Guess it depends on what the slab is for.
If it's a sidewalk it might be alright to pour over and re-do in another 30 years. If it's a structural slab, garage, etc. I'd recommend getting the garbage out and starting fresh. Provide yourself with a good base, reinforce the slab and you won't have to spend time worrying about it.
What lurch said.
If it's cracked but not heaved or settled...in other words, you won't stub your toe when stepping from one section to another...you should be fine to pour over it.
Consider using a slip sheet of some sort between the old and the new.
the new will crack in the same place, gaurrtee.