The Brew Cabin

We have a patio laid with Marshals clay cobbles, which I will have to say looks good however it is presenting us with a number of problems all related to the size of gap that has to be filled by the sand. By the nature of the cobbles the gaps for the sand are quite wide

I was told by the contractor that these would quickly silt up and the sand become quite rigid. This is to a certain extent true, but it easily dislodged by roof overhangs, even garden furniture will concentrate the drips and erode the sand. It also makes a great home for ants that cause further damage. When I raised this as an issue with the contractor, he sealed the patio, which helped to a certain extent but by now has completely disappeared. How can I keep the sand in the gaps? (Apart from the aesthetics, the loose sand ends up in our nearby swimming pool)

The patio now needs cleaning, power washing is out of the question, even using a stiff broom will dislodge the sand and also the dirty water is going to satin the sand, any suggestions here.

Finally the cobbles adjoin concrete paving slab surrounded pool. The intention was at a later stage to extend the cobbles around the pool, they have now proved completely unsuitable for that, so I have a hard edge of nice Red clay cobbles lying against rather scruffy concrete paving slabs. It looks really ugly. The problem is compounded by the fact that the slabs. Any suggestions?.

Thanks for any help

Brian Vickers

The clay cobbles shouldn't really have exceptionally wide joints. I have them for my garden paths, and the vast majority of joints are 3mm or thereabouts. There are odd spots where the joints might be, say, 10mm, but these really are odd spots here and there, not what you might call extended joints.

The sand does seal itself, but even so, ants will still mine it, and rain or regular dripping will scour the surface. The only remedy is either to use a quality sealant or to use a joint stabilising liquid, such as the Keybond by Marshalls. I've not much faith in the Keybond, and I always recommend a sealant in these situations.

I'm not too sure what you;re driving at with your final paragraph. There seems to be half a sentence missing - can you clarify?

Tony,

Thanks for the prompt and useful reply.

Is there a particular sealant that you would recommend?. I have also heard of in the past an epoxy(?) and sand based jointing compound (Geofix seems to ring a bell) have you any experience of this?

Sorry about the last para what I meant to say was "Finally the cobbles adjoin concrete paving slab surrounded pool. The intention was at a later stage to extend the cobbles around the pool, they have now proved completely unsuitable for that, so I have a hard edge of nice Red clay cobbles lying against rather scruffy concrete paving slabs. It looks really ugly. The problem is compounded by the fact that the slabs are laid over reinforced concrete. Any suggestions would be gratefully received."

I have a client on the outskirts of Liverpool who was recommended to use GeoFix on his cobbles by the previous contractor, and he's had nowt but trouble from the moment the cheque cleared. Whether it's because the prep and placement of the GeoFix wasn't done properly, or whether it was a bad batch, or even whether it was not genuine GeoFix (some naughty contractors 'dilute' it with extra sand), I cannot say for sure, but the lot is coming out next month and is being replaced.

As for extending the clay cobbles around the pool, I'd try out the sand joint with sealant - Resiblock will give you a free sample that you can try, enough for you to judge its effectiveness. As I say, try it out, and if that works (it should!!) then you could extend the clay cobbles all around as you originally proposed.
However, if you want other ideas, I'd need to see pics, so I have some idea of what we are dealing with. You can email jpgs to info AT pavingexpert.com, if you wish.

Wise words on the Geofix.

We've used it twice, and I will never use it again.

Within a couple of months, cracks appeared and the surface discoloured badly. Note that nobody could have followed the instructions more carefully than I did.

The stuff is useless - virtually zero adhesion, very little strength, allows water to filter into the base and discolours. I'm amazed they get away with selling it, as it doesn't do what it claims. It is also expensive.

Barry.

I was speaking with Mr Geofix just before xmas and he told me he had done a deal to bring over the "Sandlock" product from the US. It's supposed to be better, but then, they would say that, wouldn't they! ;)

He was to send me more info, but he never did, and I haven't seen or heard from him since. That's not really the best way to get your products used within the trade.

Does anyone have any success stories with Geofix?

I've taken some pics today of some desperately bad geofix, used to joint around reclaimed setts. I'll be building them into a page at some point, but, having seen the mess it's made of what was a bloody expensive job, I'd be very reluctant to recommend it's use on any joints wider than 4-6mm. :(