I'm considering laying a limecrete patio slab. I'm considering it for 2 reasons:
1. I have neither a damp proof course nor damp proof membrane in my house, and I'm concerned that a concrete slab next to it might cause some damp.
2. Sometime in the future, I may be able to afford a little conservatory on it, so I might as wall do the slab now while I'm working on the patio anyway.
I'd rather not risk causing damp, but I'd also rather not risk the slab not setting. I may end up putting a very small amount of cement in the otherwise 6 ballast to 1 hydrated lime mix.