Decorative gravel (Cotswolds Buff) over tarmac

[Nataliewrigley]

Hi, we have a large are of tarmac in our garden. We want to lay Cotswolds Buff aggregate over it but everywhere on Google says not to! Really reluctant to dig the tarmac up and the cost of gravel grids for the area is sky high so I’m looking for any success stories of people laying gravel straight onto tarmac/concrete?

I must add, cars will not be driving over the area!

If it won't be getting compacted into the resin, then I don't see any problem.

I bought 3 bags of this a couple of weeks ago:
https://brisks.co.uk/products/20mm-cotswold-chippings

It's added a load of brightness to my driveway!

Op it won’t work, you need a gravel grid, it will just move and shift, both of someone walks on it, or if you drive on it, it will be both slippy and wash/move away and leave large parts of the tarmac exposed.

^^ This.
Very impractical and will look a mess I’m afraid. Gravel shifts too easily on a hard surface.

This ^

It really really won't work

Echo the above.

Also it doesn't stay nice and creamy colored for very long, maybe two years. Then it gets dirty and goes grey.

To be honest, it doesn’t do that, we have a gravel driveway. We do need to top it up every couple of years or so, it’s laid on a hard core base. But it absolutely doesnt change colour. I don’t think anyone’s does, as you see lots of them, and no one completely removes and starts again , if it is grey it started that colour, it would only be things like white painted pebble that did that.

Well mine did, and it's not easy to pressure wash gravel

How odd. Mine hasn’t, nor any of my neighbours. Never heard of that. I mean I guess if it’s down long enough and not topped up it could get covered in dirt, hence giving that impression , but not after two years. Very weird.

Ours went green due all the rain/damp!
Admittedly this was a small area of a north facing garden but still worth considering if you get a lot of rain.

It's more like surface dirt /algae
The years pass quickly so maybe it was 3-4 years not two, but it definitely does get dirty and then the effect is less gold /buff and more greyish. This is in a south facing garden with no foot or vehicles going on it.

I think this is what we had outside the back door laid over concrete/slate flags, it was bloody awful, and created a lot of dust that came in on our shoes. It was the worst gravel ever.

Actually I think it’s a good point, as I can only see the issue would be due to poor drainage, otherwise I guess the rain washes it clean, or it does mine anyways.

Mine is on hard core though , so there is no dirt under it, and we top up every 2- 3 years which keeps it fresh, ours dissipates, Christ knows where it goes to be honest. 😂

The op would have shocking drainage I think if it’s on tarmac. But she can’t do it with out grids anyways. It would be slippy and look terrible within a week or two of laying.

Yeah it kind of wears down and turns to dust doesn't it? It's about a foot deep in places (had to level my garden out) so I don't think it's a drainage issue. But I don't go out and turn it regularly. Looked great when new though.

Thanks for the replies.

gravel grids it is then.

JJathome do you have Cotswolds Buff? I’m worried that it’s going to discolour and/or turn to powder now looking at these comments!

Any help, really appreciated.

Cotswold Buff is a softish Limestone chipping and will break down over time. Being Limestone it also absorbs water which causes discoloration. You could try a light coloured gravel such as 20mm Harvest Gravel which is much harder and won't discolour.