| Comment | Have a look and see what different substrate materials you can get your hands on for cheap - if you were gonna do it and lift the floors, it might also be worth your while to buy a whole bunch of those foam pad things covered in cones for putting sound dampening on walls and cut them to shape and put them in the cavity ahead of any substrate cone side down - they are relatively cheap, and definitely cheaper than something like cork mulch, so would minimise the amount of substrate you'd need to add on top to fill the cavity whilst offering similar sound deadening properties. |
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