Hi,
We’re putting down porcelain tile over a 1935 basement concrete slab. We had not originally planned to demo any part of the slab and so we were not planning to use an uncoupling membrane, but alas, we ran into some issues and ended up replacing the sewer line and putting in a sump pump. Since we now have newer concrete patches throughout the basement, should we be putting down an uncoupling membrane before tiling? I’m worried we will get cracking in the new concrete which will then transfer to the tile. Thanks.