Yes I was talking about the dynapad. The idea is to put down the butyl sound later with foil (dynamat or kilmat or similar) over as much or as little of the car as you want. I’m planning on doing as close to 100% coverage in the cabin as possible. Underside of the dash, floor pans, doors, kick panels, firewall, package tray, roof; as well as most of the trunk (sides, spare tire compartment, deck lid, wheel wells.
Those thin 80 mil sheets are advertised to Insulate some, but primarily be a sound barrier, so they suggest you put something else to do more actual insulation. Noico makes Noico Red, which is 150 mils thick, but is not dense. They advertise it for the deck lid and trunk, as well roof, and firewall. Someplace where it won’t get mushed around (like under your feet). Then Dynamat makes Dynapad which comes in thicknesses of: 1/8”, 1/4”, and 1/2”. It’s dense and is supposed to be used in the same places as Noico Red, but also under carpet. I was considering doing kilmat everywhere, and then Dynapad in 1/8” under the carpet where your feet sit and on the firewall and roof.
But that’s just a theory. Kilmat is cheap so I can easily do 100% coverage. But Dynapad is significantly more expensive, so I will not do nearly 100% coverage. I don’t plan on adding jute under the carpet if I add another layer of insulator/sound deadening.