Can’t go wrong with the uni clic system
Why didn’t you overlay with 6mm plywood ? Is every plank cut exact ?
What’s the problem ? It all needs digging up and redoing. Won’t the builder do that ?
Been using f48 plus a lot as Harvey Maria recommends it. Found it a good HT. decent open time as well.
You could use Jumpax over the floor. Not ideal but will work
You can use F3 or F44 for glueing down the regupol though
Just do it right and use sp101 5.5mm plywood then feather screed the joints and then the LVT
You don’t need impact noise reduction as no one...
Just use a cheap foam one with no Barrier on it as you don’t need one.
I use 19mm ring nails and they only go in a bit so 16mm screws would be ok.
Gone over a few and just used Timbermate excel underlay with no issues
Go for a decent quickstep laminate
Both water resistant top finish and decent
I’d use a SDS drill on it
Have you tried Dave Merrilees
Needs grinding then a coat of ardex RE3 epoxy primer sand blinded , then smoothing compound