Cheap as possible large vermiculite chips blown in the floors between joists via small routed out holes hole and fill the wall with the same blower from the top between the uprights . If you haven't got a 3D printer find a pal quickly and ask them to make lipped plates for the floor (Thingyverse prints ) for you
For plugs for the walls use the hole saw cut out . Tie a lolly pop thick /sized stick to a cord , thread the cord through the hole in the disck Put a streak of Evo-stick or similar on the stick so it gets pulled to the plaster board . Insert the stick in the hole, push the cut out down the string & into thehole & pull the cord till the cut out is now flush with the rest of the wall . Slip a bit of lolly stick to the base so you get the cut out central then slide a well pointed bit of welding rod or a big safety pin through the cord to hold it in place till the glue sets snip off the cord , push the tail back into the hole then carefully fill in the gap & hole . If you really feel the need for a stronger patch ease an 8 mm cut batton in to the hole , pull it tight to the board and use bell ended plasterboard screws to hold it and then glue the cut out to the backing stick and add a pair of bell end board screws to hold it .
There are numerous tube videos showing this sort of vermiculite filling been blown in and again there are numerous Thingyverse blower nozzles to get it done.
Our old semi detached bungalow had dozens of such wall patches put in by me where I'd vermiculite filled the dividing plaster board walls between us & next door .2 boards a vapour barrier , the studding , a vapour barrier then two boards on their side . The old couple next door. snored like an underground train and were constantly moaning & arguing with each other , plus being age related deaf their TV drowned out ours if we were ( Usually ) on a different channel it sent me potty .
I'd seen how good it was for wall insulation & sound deadening between rooms in my brothers 3 bed stud wall house , so we did the bedroom floors , turning the hole blanks up out of ply on his lather
Their snoring sent me potty & drove me to take those steps
I actually made the blower out of glued up plyboard as 3D printer hadn't been invented at that time and used an old plastic dustbin as the vermiculite hopper ./ the air flow was an arrangement of a VAX vacuum cleaner set in a sealable screw top barrel with the air inlet pipe set in the wall with mastic and the outlet a 6 mtr length of pond pipe to the gun
The Vermiculite .. I found a home & business insulation company who used it an got it for less than £20 a 100 litre bag back in 2002
hi dapph, thanks for posting!
I never knew vermiculite could be used for sound proofing!
No doubt I'll be building stud walls next to further reduce noise, so could be an option to fill wall with vermiculite, as I would have access to I guess you could fill from the top and compact it for more density...
Cheers