pouring new concrete over old?

Old 10-01-19, 02:25 PM
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pouring new concrete over old?

Our house has had a 2Ē slab poured over the first one(not sure why they did this? maybe to level it). It was poured in 1984 so it has heaved a little and instead of grinding down the high spots so i can finish the basement i would like to remove the old layer of concrete(which breaks off fairly easy). I plan on installing a sump pit and backwater. Now my question is i was thinking of pouring a 1Ē skim coat to level everything after. Are there any extra steps to take or can i just pour on top? There is slope towards the drain. Can i pour the new concrete flat without slope since i will have a sump pit? I realize itís a lot of work but the main issue is we canít afford to loose any more headroom

just a little more info I plan on installing dmx with 5/8 osb and lvp and spray foam 2Ē on the block walls at the end the concrete under the first layer is about 3Ē
Old 10-01-19, 04:23 PM
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which breaks off fairly easy
You already know the answer to part of the question, the new and old do not actually bond so there will always be a joint there.

Actually it's recommend that you isolate the two, assuming the original is SOLID. And nothing less than 2"


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