I was about to add a bell cast bead to a wall on my early 60's quirky house. But there is a gap between the wall and the paving. I could just fill it with cement but it looks deliberate somehow so I don't want to add more problems to an already damp house. I can't tell if there ever was a DPC. I don't think so and in Cornwall, vinyl tiles stuck on to a solid floor often passes for one! Anyway, my question is, looking at the pic below, should I be filling the 10mm gap (which is about 20-30mm) deep) before adding the missing drip bell above? The gap isn't new, I think someone had added a crude cement fillet in the past which has broken up and disappeared over the years.