In my bid to take over this part of the forum with all my garden related queries here is a bit of a worrying one - well worrying to me anyway!!
Background info : Patio has been down 3 or 4 weeks now - all seems very solid (laid on 3-4 inches MOT and 2-3 inches sand/cement) Slabs are 600x600 concrete, laid with 5mm or so gap brushed in with kiln dried sand.
Slabs are 2 shades of same type - light coloured ones as a border, and slightly darker ones in the middle - the slabs are obviously part of seperate batches.
Anyway noticed yesterday a hairline crack on about 3 of the lighter slabs. It starts about half way along one edge and extends about 8 or nine inches in towards the middle, not quite at 90 degrees but almost. Now these slabs don't seem to move at all or anything like that.
Today when out in garden I noticed 2 more (so 5 in total) with almost exactly the same crack in almost exactly the same place. Coincidentally 3 affected slabs are in a row, the other 2 a few slabs away (not in part of same row)
I reckon to myself I got part of a bad or damaged batch for this same crack to appear multiple times - does that sound feasible? I did reject and put aside one or two of the same coloured slabs because they had a similar crack that was noticable before laying. None of these showed any signs though at that point.
I was thinking of moaning to builders merchant but not sure how receptive they will be. I also paid for these to be put down (and they seem to be down very well) so would have to pay for remedial works.
Any advice? Does it sound like dodgy slabs? WHat should I do to ensure I have comeback if more go the same way? Could it be change in temperature / moisture conditions that is suddenly bringing this to light?
Cheers.
Chris
Background info : Patio has been down 3 or 4 weeks now - all seems very solid (laid on 3-4 inches MOT and 2-3 inches sand/cement) Slabs are 600x600 concrete, laid with 5mm or so gap brushed in with kiln dried sand.
Slabs are 2 shades of same type - light coloured ones as a border, and slightly darker ones in the middle - the slabs are obviously part of seperate batches.
Anyway noticed yesterday a hairline crack on about 3 of the lighter slabs. It starts about half way along one edge and extends about 8 or nine inches in towards the middle, not quite at 90 degrees but almost. Now these slabs don't seem to move at all or anything like that.
Today when out in garden I noticed 2 more (so 5 in total) with almost exactly the same crack in almost exactly the same place. Coincidentally 3 affected slabs are in a row, the other 2 a few slabs away (not in part of same row)
I reckon to myself I got part of a bad or damaged batch for this same crack to appear multiple times - does that sound feasible? I did reject and put aside one or two of the same coloured slabs because they had a similar crack that was noticable before laying. None of these showed any signs though at that point.
I was thinking of moaning to builders merchant but not sure how receptive they will be. I also paid for these to be put down (and they seem to be down very well) so would have to pay for remedial works.
Any advice? Does it sound like dodgy slabs? WHat should I do to ensure I have comeback if more go the same way? Could it be change in temperature / moisture conditions that is suddenly bringing this to light?
Cheers.
Chris
