I layed granite slabs (the long narrow type about 20mm deep) onto a 4" sand/cement mix last year. The screed was directly on top of a sound slab patio which had been down 30 odd years.
I have recently run a narrow channel through it and so lifted slabs as necessary whilst building an extension adjacent necessitating a drain. I have made good the channel and took a long time to ensure the surface was level and smooth with the surrounding base level. Further slabs have cement splash staining and will need changing and I also wish to widen the patio one more slab for aesthetic reasons.
I dont really want to rip up what is a perfectly good base at the moment so my question is how to relay these slabs without raising the level too much. I did drop a few slabs back to where they had been lifted but it was clear the type of slab is machined and imperfections in height are unforgiving so I suspect I will need to lift all and lay onto a thin spread of some kind of manufactured compound rather than a screed.
Any thoughts or suggestions from those with experience of this? I realise that lifting the base would be the best suggestion but I have a thousand jobs to do so have money and time constraints which dictate my need to re-lay as is.
I have recently run a narrow channel through it and so lifted slabs as necessary whilst building an extension adjacent necessitating a drain. I have made good the channel and took a long time to ensure the surface was level and smooth with the surrounding base level. Further slabs have cement splash staining and will need changing and I also wish to widen the patio one more slab for aesthetic reasons.
I dont really want to rip up what is a perfectly good base at the moment so my question is how to relay these slabs without raising the level too much. I did drop a few slabs back to where they had been lifted but it was clear the type of slab is machined and imperfections in height are unforgiving so I suspect I will need to lift all and lay onto a thin spread of some kind of manufactured compound rather than a screed.
Any thoughts or suggestions from those with experience of this? I realise that lifting the base would be the best suggestion but I have a thousand jobs to do so have money and time constraints which dictate my need to re-lay as is.