In an upstairs bedroom, super squeaky tongue and groove planks were removed, and large panels were put in. I used that expensive tape on the joists, the panels were all cut to fit with tiny gaps by the walls. One by one they were glued and screwed down. The finish is nice, and new laminate/carpet possibilities are exiting.
Problem: footfall on that floor is drum-like now. The joists are 5 meter/yards long, and that is a long unimpeded space for a percussion effect. I should have put some sound insulation in when I had the floorboards up. It's all glued now, though.
What can I do from below (through the plaster ceiling panels), or from above (through 22mm boards)? I'm hoping there's a minimal expanding foam injection I can do - and not have to fill the whole void, just here and there to break that 5 meter/yard "note". Then repair the holes of course.
Update [Jan 2021].
We redid the ceiling below with new panels. The previous lot were nailed up 30 years and had stippling applied as that was popular at the time. We'd tried a plaster skim over that 10 years back, and cracks were emerging as not enough PVA had been applied by the plasterer at the time. The new panels are screwed up, taped, jointed and painted.
At the same time we stuffed up rock-wool between the joists. The drum sound is a little less :( We've not done new carpet upstairs yet - pandemic slowness.