Mark S. wrote:
A while ago I took off the top inch of loose concrete on the ground
floor of my project.

I levelled it with compound to cover the dust/roughness more than
anything else.

It's been left about 12 months and there's a few patches where the
compound has lifted off and there's what I suspect is "salt"
underneath?

I think the damp course was a layer of tar like paint that had been
under the skim level that had become detatched/broken up.

Is it possible to fix it using anything within the inch or so that's
"spare" or is it a job I really could do without doing that needs
doing? :-(

Just managed to save some money to get some work done on it too.

Mark.

Your new membrance gcan go on top,it doesnt need to be 1" down. Salt
only shows up when water evaporates, leaving the salts behind. Top the
slab with a sealer and it wont dry, so no salts form. Concrete likes
being wet, as long as its not wet & frozen.

NT