Roof, including chimney stack, is being scaffolded for flashing repairs and I want to make the most of the scaffolding, so I’m planning on getting my hetas guy to drop the liners at that point.
4 chimney pots on the top - each fireplace had a separate run up the chimney. I will have two liners installed, one per appliance.
I cannot drill through the hearth and access the floor void so the external air supply will have to draw from the room. Unless, as I said earlier, I can draw from outside using a concentric flue liner, if such a thing exists.