I know damp can be a seriously hot topic but just trying to firm up some ideas.
I am modernising an end of terrace (at the bottom of a hill) stone walls (450mm thick, probably rubble filled) 3 bed in Wales. I'm living there at the moment. No Heating, earth floor in one room, crittle windows, it's fun :D
Damp is not too noticeable because there's no heating/hot water but I know it will be... There's all kinds of problems that will be dealt with from down pipes going nowhere to concrete gulley/drains that are messy and leaking.... Lot's of woodlice crawling around...
Anyway... Almost all the houses here have pebble dash render with a belling at the bottom then smooth render set in (thinner than the pebble dash) below to the ground.
Surely this is bad! I've just down some exploratory digging/hacking and found a single even course (assuming it's a slate type dpc), and an entire eco-system living behind the cement render, that is approx 180mm below the approximate final interior floor level. Quite convenient because having to take out that much to put a slab in the room with the earth floor so will tie up with DPC quite nicely.
So scene set. Surely, on the outside, the stone should be exposed and not rendered from the about 4" above the DPC and not all the way to the ground (bridging the DPC) on the outside like all the hundreds of other houses around here.
Hopefully that made sense :D
If we get a simple response we can move on to dpm detailing around existing slabs ;)