Gravel driveway + building a hump using setts

[mike673]

I am looking to build a gravel driveway for my home and I would like to construct a slight hump at the front of the drive using setts to stop the gravel from escaping onto the public footpath.

I plan to build the driveway on 150mm of type 3, then 50mm bed of sand and then use one of those honey comb grids on top of the sand to contain the gravel.

Now the only thing I am unsure of is how to construct the hump? I’ve read the sett laying guide on the main website and it says to lay them on 100mm bedding layer. But I am unsure whether I would need a sub-base for the setts or not? The setts are 100mm x 100mm x 200mm and the hump will be about 1m depth x 12m in width, across the front of the drive. Also would I need some form of restraint on the driveway side to support the setts?

Hopefully that makes sense?

Any advice would be greatly appreciated. Thanks, Mike

[rab1]

For a start dont use type 3, use type one for the base.

[mike673]

But isnt type 3 free draining??

[rab1]

unless you use a teram type layer over the type 3 the sand will clog it up.

[mike673]

Yes i was going to use a geotextile. Its just that dont want to have to mess about installing drainage.

[rab1]

as long as your sub base is well compacted then lay them as per the site instructions. I thought you were just going to whack the type3 and then just put the sand down on top of the stone.

[seanandruby]

1 metre deep. Are you sure ???

[mike673]

as long as your sub base is well compacted then lay them as per the site instructions. I thought you were just going to whack the type3 and then just put the sand down on top of the stone

But what I am confused about is if I lay the setts on 100mm bed on top of the sub-base then I'm going to have a gap of around 90mm between the setts and the gravel on the driveway. Apologies for the badly drawn diagram but I think it may better explain what I mean (its not quite to scale)

1 metre deep. Are you sure

When I say 1m depth I mean 1m from the edge of the drive towards the house. So if we were viewing the driveway from above the below diagram will show you what I mean




I am just overthinking this?

[GB_Groundworks]

It depends on your ground if IRS good stiff ground then you can bed your 100mm bedding on it then your sets, or just excavate deeper where your threshold (hump) will be.

What's the sand for? I can't see it serving any purpose

[mike673]

Well ive seen a couple of videos and they used sand. I have to be honest i didnt really see the purpose either but just assumed it was the done thing. So do you think it would be ok to do away with the sand? It would save me time and money as well.

If i was to do it the way you described would i need to provide any kind of support to the edge of setts where they meet with the gravel?

[GB_Groundworks]

Yes see haunching on the main site

[mike673]

Thanks GB its much clearer in my mind now. And thanks to everyone else for helping

[mickavalon]

The sand bed get's the grids nice and level. It's a lot easier than trying to sit the grids flat on sub-base material, besides you need them laid well or they won't work, they'll fail without the right support under them.