Loose paving slabs - How to fix newly laid loose paving slabs

[Tony McC]

See this page

[milleniumaire]

Thanks for the link Tony, I had already seen and read that page and it was very useful. Last night I checked the DPC height and where the slabs have been re-layed it is around 140mm higher than the slabs. Around the side of the house the existing slabs are currently between 150mm and 140mm lower than the DPC, so raising them will reduce this.

I'm not particularly concerned as the previous patio, which had been down for around 15 years was at a similar height and there's no sign of issues.

Last year, I cleaned up all my stone window sills and treated them with some Kingfisher Extreme Climate Sealant and they are still clean and water proof. I will probably use some of this on the lower part of the stone wall just to give it a little extra protection although I'm fairly sure it doesn't need it.

So far so good for the newly laid slabs. They are now completely solid so feeling much happier. It has also been an opportunity to fix a few "anomolies" in the levels so they will be even better than before! Nothing we couldn't have lived with, but still an improvement.

[Tony McC]

Check that the sealant you propose is actually suitable for paving. Some of the masonry sealants don't cope well with trafficking and can abrade quite quickly.

[milleniumaire]

It's now May 2018 (where does all the time go?) and when we had that welcomed short sunny spell a few weeks ago we did some work in the garden and noticed that a number of slabs appear to have moved. This is evident by the cracks along one side of the resin joints, where the resin has stuck to one slab but not the adjacent slab. ALL the coping slabs are loose and can be moved. Obviously this is very disappointing as the slabs were taken up and re-laid by the builder but there is still an issue.

I'm considering my options, which may include contacting the builder and asking for some money back to pay for the flags to be taken up and re-laid. The trouble with this option is that I just don't want anything to do with him as he is clearly a cowboy who hasn't a clue what he is doing (although to be fair, random stone walls he built haven't fallen down yet!). The other issue is the length of time it would take to sue him and the potential cost, as I'm sure he won't be wiling to give us a refund. I'm also not sure if he is insured.

What I would really like to do is name and shame him and hopefully ensure others don't use this guy for landscaping.

Going forward, I will probably end up removing the slabs myself, removing the dabs (see my other post regarding the use of resin jointing) and taking it back down to the "first" solid layer, then using a SBR slurry to re-lay them.

I may wait another year before doing this or split the job over a couple of years. As it is the patio is useable, but needs sealing to protect the Indian Sandstone.

[lutonlagerlout]

its a tragedy
so many cowboys out there
but also good honest reliable people too
so often I price work and am asked why is it so expensive?
"err to do everything correct the first time is far cheaper than doing it wrong then having to redo it "
I hope it works out ok for you
LLL

[ChrisGJ]

Hi.... I read this post with interest and have used this site a number of times for advice (thanks very much - sadly largely after the "event" hence this question)...

3 years ago we had approx. 60msq of slate paving (modern style smooth-ish slate 600 x 300). We used a local guy recommended to me. He assured me it was laid on a full mortar bed but that simply cannot be possible if you tap a slab and it sounds hollow can it?).

Now, some of the slabs have very tiny movement that constantly annoy me when I stand on them. Even the hollow sound reminds me that this probably hasn't been done correctly and as promised.

Reading that the only way to truly fix this is to lift the slabs and start again....my question is; is that really viable? i.e. wouldn't the slabs break?

thanks
Chris

[ChrisGJ]

also, the ants seem to love the joints and probably cavities underneath them - why wouldn't they?! - which again suggests it can't be a solid bed can it?

[lutonlagerlout]

its viable of course, but time consuming
hollow sounds can happen with full beds
but are much more likely with dots and dabs
ants live in the garden but generally require voids and cavities to live in

LLL

[ChrisGJ]

thanks. most of the patio is fine, just a few slabs with the tell-tale sound / feel when you walk on them that probably bigger movement will eventually happen. guess I either have to get over it or sort it out

[milleniumaire]

After using our patio for the last few months now almost every single joint has a crack line down the expensive vdw 815 plus epxoy resin joint filler, even where the slabs appear to be solid i.e. no obvious sign of movement. Quite a few slabs are obviously moving and many others also sound hollow. Around these slabs the epoxy resin has cracked alongside both slabs and in a few places it is loose to the touch. All very disappointing, not to mention expensive as we chose this resin due to the small 5mm gap and to ensure longevity as we were sick of having to re-mortar our previous patio. Obviously the resin has broken a new record by becoming loose within 6 months! Not what we expected and I'm really surprised at what appears to be a very poor bond between the resin and the edge of the slab. I appreciate that a large part of the problem is due to the poor way in which the slabs have been laid, but even in a few places where they are solid and there is no traffic, the resin still appears to have cracked away from the edge of the slabs.

Our plan is to leave the patio this year to enable the slabs and the resin to work loose and next year the patio will be lifted and re-laid. At this stage I'm not sure I would use the vdw 815 again, we may try a different resin.