Let me explain what you are looking at.. it is a rather fabulous Grade II*.
The house is early C18 but this floor is, we think, C19. The house had a lot of alteration done late C19. The floor joists have battens running the full length and then small strips of wood (not unlike the concept of a lath and plaster ceiling, but much thicker, like battens) spanning across the gap. Lime has then been poured into the space to fill up to the upper part of the floor joist. It then has floor boards on top. The surface is rough, so it was never supposed to be seen or finished. On top of the floor boards, probably C20, are strips of wood to look like parquet flooring.
The floor feels solid. It doesn’t resonate in that way that a normal suspended floor does. It has no bounce and is absolutely solid when banged – not unlike a modern suspended concrete beam and block floor. The lime is a mixture like a mortar, but its not actually mortar.. its more fragile, like a lime putty, and about 2-3 inches deep.
It is quite remarkable.
The problem is that there are two extensive areas of dry rot. We have devised a way to access the floor externally by removing two sections of wall that can then be reinstated. We don’t want to lose any of this floor and need to treat it in-situ.