On Friday, 31 January 2020 13:57:48 UTC, GB wrote:
On 31/01/2020 12:52, newshound wrote:

I think I would be inclined to be drilling and injecting silicone to
provide a full thickness barrier.


Is that a DIY job?

Given solid concrete floors, how do you drill down low enough into the wall?

You can hire the equipment and chemical from tool hire shop.
Two holes per brick and bang plenty in.

If it's a cavity wall, the cavity may be full of cement/rubble etc.
You need to make a hole big enough to get your hand in and have a look with a light and mirror. If it's full of crap you will have to rake it all out. The cavity should go well below the floor. (The crap may be bridging the damp course.)