I've got a local block paving/flagging firm here today and I'm not convinced that they are doing a proper job.
The deal was to remove the old concrete flags (which they have done), then to dig out the area, the boss said he'd dig out 100mm of whatever it is underneath and replace it with MOT and then add a 60mm layer of the sandy stuff on top (sorry, I forgot the name of it).
Anyway, it turns out that the old flags were laid on cinders, these cinders are at least 12" deep and are really soft like sand - that's why the old flags were moving around.
Anyway, I noticed that they had started to put the MOT down without digging any of the cinders out and I'm worried that I'll end up with a sagging patio and pathway.
They have whacker plated some of it, but I went and had a look and I was able to leave a footprint of about 1" deep in places and areas such as grids and edges are especially soft, so I'm guessing that's all wrong?
I asked them about it and got very vague answers, so I thought that you guys would be able to help me out?
The job consists of a garden path around 1.2m wide which runs from the garden gate, round the front and side of the house, finishing up with a patio. The path is going to be block paving and the patio is indian stone.
I can do photos of the current state of play if required.
Bit of a grey area really. He will do whats agreed ,but it will leave your drive with pools and dips over time.
Im not sure how the other lads would deal with it, but it looks like your going to be paying out more if you want 300mm of cinders digging out and replacing with MOT.
Yes, I'm not expecting the firm to go out of pocket, but then again, I don't want them to do less work than was agreed and still keep the same price.
I have a written estimate, but that didn't include the indian stone as originally it was going to be all blocks. It doesn't say what depth they would dig to on the estimate though, just "remove old flags and prepare ground ready for block paving"
Could I just ask, should I be able to put footprints into the MOT after it's been whackered? Some areas of it feel really hard and compressed and others just go to mush.
It doesn't matter what was agreed, I can't imagine putting MOT on top of loose cinders. Absolutely pointless.
Just done a job to re-lay crazy yorkstone paving which had moved a lot over 30 years. Spec'd 100mm sub as usual. When we lifted the old paving the slabs were laid on mortar straight onto the peat soil. Soft as sponge. We dug out an extra 12" before we hit firm sub grade.
The point is that I would no sooner have put MOT on top of an unstable sub grade than I would fly to the moon. We agreed the remedy (extra coarse hardcore then extra MOT, wackered in 100mm layers) and the cost involved before cracking on.
My advice would be that if they're not willing to dig out the cinders and re-instate (at an agreed price of course) then pay them for what they've done and get them off the job.
Had it out with the boss this morning, he agrees that some of it isn't up to scratch and is going to dig out the front part.
I showed him the back area where I was able to leave half inch footprints in parts of it and he said he's ordered another ton of MOT and they'll whacker that down and it should be ok. He also went on to say that because the back area is having Indian stone on it, the preparation is different somehow and that once the cement has set, it's not going to move.
Extra MOT is unlikely to help. The sub-grade needs to be firm in the first place. You can use a suitable geo-textile membrane under the MOT if there is the odd suspect spot but not with larger areas.
As DNG says, preparation is no different. If the sub-base has movement just from your own body weight, the paving WILL fail.
Yes, unfortunately, he was lying to me. They just went ahead and did it, but in the parts I can see, it is now quite hard, even though its all waterlogged.
Some of the flags are very uneven - I realise there's going to be natural variation in the stone, but this doesn't look right to me.
The large flag, bottom right has sunk about 1-2 cm and you can see that two of the flags are touching so they won't be able to add pointing there - is that normal practice?
A few more of the pics from the job can be found here.
