I did what sokka mentioned. rockwool at both the top and bottom. The chimney is still present so there's a cast iron 4" pipe which is my conduit. When the previ

I did what sokka mentioned. rockwool at both the top and bottom. The chimney is still present so there's a cast iron 4" pipe which is my conduit. When the previous owner decomissioned the oil tank they chopped the top and bottom of the chimney off and added caps at both ends and the roof was patched. All the cables go all the way through to the attic and I hit the second floor from the attic. Not sure it'll be to the liking of all inspectors but to me it's reasonable.