We have recently discovered that the neighbours paved path is a few cm above our DPC. There is a gully between their path and our wall, filled with gravel - presumably to act as a French drain. However, the top of the gravel is around 8cm above our DPC rather than the often-quoted 150mm below it. I have uploaded a photo showing this.
![Image](https://i.ibb.co/dk2g4DW/IMG-20241103-123156.jpg)
Our neighbour is lovely and it was the previous owners who must have installed the path, so we're keen to explore the simplest and most cost effective solution. I had wondered whether I could install chemical DPC rods on the next level up, but then I thought that this may be too high and the damp would continue to come through the wall below it.
So today I drilled an exploratory hole through the mortar in the brick course above the existing DPC and found that the DPC is around 7cm above the internal floor. This was never a problem until the path was laid bridging the DPC, but I don't think creating another higher DPC would achieve anything as damp isn't rising far up the wall anyway and it's mostly the bottom and skirting that are the most damp.
I would very much welcome any suggestions that would avoid lowering the path or perhaps even digging a much deeper gully - which the neighbour isn't keen on as she feels it might be a hazard, as well as being a big job. I've read that one possible solution might be to dig down to a couple of courses below the DPC, clear the soil from the wall and then install a membrane against the wall (perhaps flashing or a roll of DPC standing up as a baffle) and then backfill with gravel. Does this sound like a good idea or a terrible one?
Obviously, any better suggestions would be greatly appreciated!
Many thanks