Hi, I'm trying to rescue a very large (5m x 2m) old stone flag (circa 1860) that has unfortunately fragmented in to circa 9 pieces. It should sit approximately 4" off the ground and overhang some stone edging strips that sit underneath around the perimeter. I don't know how the stone was supported in the past, but the centre appears to have collapsed.
I have a photo but can't figure out how to attach it to this post.
I'm thinking of lifting it all up, excavating 4", laying MOT1 to be flush with ground. I'll then build a 4" high semi-dry cement / sand mix inside the stone edging pieces to create a concrete slab. The stone flags would then be placed on the semi-dry mix and left to settle. I'll then point the gaps with a lime mortar.
Does this sound sensible please?
Anything I need to be wary or careful of?
Thank you
Rescuing old stone flag - Sub-base and bed advice
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Tony McC
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Another reader doubling my workload by posting here *and* emailing the very same query. Thanks for that!
On what will the edgings sit?
The simplest fix is to build a C.7.5/ST1 concrete (NOT sand/cement - too weak) base within the edgings to support the flagstone pieces, which can either be bedded directly onto the concrete or onto a mortar bed atop the concrete.
https://www.pavingexpert.com/mortars#mixing-on-site
On what will the edgings sit?
The simplest fix is to build a C.7.5/ST1 concrete (NOT sand/cement - too weak) base within the edgings to support the flagstone pieces, which can either be bedded directly onto the concrete or onto a mortar bed atop the concrete.
https://www.pavingexpert.com/mortars#mixing-on-site
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