gravel driveway has hills!

K

kittyjo

Registered User
Messages
25
I put down gravel in my steep driveway 4 years ago but ever since its been bunching up into mounds. Raking it (which was back breaking work!)did no good as a few cars later and its right back to mountains. I always assumed that it was cos there was too much gravel but a builder recently said that maybe there wasn't enough hardcore put down intially. What does this mean and what can I do to get it fixed? I bought the house as a finished product - can I get the builder back?
I'm desperate now cos even the postman won't come down it!
 
Gravel will shift when there is passage over it, especially when on a gradient.

Ours bunches up around the edge where cars/walking happen less often, and usual parking spots will leave a track.

Could it be the nature of the beast?
Get a rake to it?
 
Kittyjo,

I was in Roadstone yesterday pricing some Indian Sandstone and saw a brochure for a product that is supposed to handle such situations, even works on gradients up to 45% according to the blurb. It's a plastic/pvc honeycomb that is laid under the stone and because of the hundreds/thousands of small compartments that the stone falls into, it adds stability and you have less movement. I was just intrigued by it because I have a small stoned area in my back garden that I am going to lay a patio on mainly because of the 'shifting stones' problem.

Anyway, I have no information on how effective it is but it might be worth a look.

All the best.

kittyjo said:
I put down gravel in my steep driveway 4 years ago but ever since its been bunching up into mounds. Raking it (which was back breaking work!)did no good as a few cars later and its right back to mountains. I always assumed that it was cos there was too much gravel but a builder recently said that maybe there wasn't enough hardcore put down intially. What does this mean and what can I do to get it fixed? I bought the house as a finished product - can I get the builder back?
I'm desperate now cos even the postman won't come down it!
Click to expand...
 
I don't think hardcore is the problem, unless the gravel is sliding into hollows. From what you describe, it sounds like the gradient and/or traffic is the cause of shifting gravel. Gravel is loose and will move under pressure. You will be familiar with tracks in older gravelled drives. Also, it may be that too much gravel was spread, hence yopur "mountains". I'm no expert, though, others might have other reasons.
 
Last edited:
It can be down to the type of gravel too. Washed pebble will tend to move around a bit more than crushed stone, which tend to bind together better.

If it is crused stone (you will know because it will have rough edges) maybe the hire of a vibrating roller might improve the situation. If you have pebble, then just buy a good rake.
 
Welfarite said:
I don't think hardcore is the problem, unless the gravel is sliding into hollows.
Click to expand...

This is what is happening Welfarite. If I removed all the gravel the driveway would be all holes!
Actually I think gravel is the wrong word - its stone chips - sorry bout that!
 
As you can see there may well be a number of factors causing your pebble/stone to ridge. Common causes are :

1. Too much top dressing, a typical dressing should be 25 - 35mm deep over a blinded hardcore base. If the latter is not done correctly, mixing of hardcore and top dressing usually takes place and is very difficult to correct. It is not uncommon to see 100 mm - 150 mm topdressing layer, far too much and constant ridging is the result. Only remedy is to remove excess top dressing.
2. Material - is it a stone or is it a pebble? Given their general rounded shape, Pebbles are not suitable for driveways/walkway areas because they do not lock in or bind. Wrong use of stone is a common cause of ridging. A chipped stone ie with straight/sharp edges are much more suitable because they compact/bind well and once embedded and compacted they remain in situ. Of course an ocassional rake over of top dressing is required but only now and then.
3. Size Matters - choice ranges from 5mm - 50mm, 14-18mm is perhaps most popular size, but 20mm also becoming increasingly popular. Very small can 'disappear' and require topping up, especially if the hardcore/sub-base is any way soft or soil is nearby. 25mm+ is fine for driving but difficult to walk on with any degree of comfort.
4. Colour - subjective perhaps, but colour should compliment house and yet be practical. Not very practical to have light colour stone surrounded by lots of deciduous plant/tree stock. Fallen leaf must be factored in to colour selection.
5. Inclines - it is possible to design and structure an area to minimise/prevent top dressing drifting on inclines. There are also a number of proprietary meshes available to prevent stone movement, however these can be very expensive to install and are no guarantee to provide an absolute drift free surface.
 
You must log in or register to reply here.
Back
Top