Gravel Driveways?

[JDub]

In a few weeks I am getting an area (next to my existing Driveway and carport) excavated to make it a more usable space.

It involves digging into an embankment about 800mm after which I will lay one of those pre fabbed DIY retaining walls.:cool:

I wish to use this newly excavated area as a parking area etc.

What type of gravel should I be using for the job?
I see alot of the red/orange stuff around my area ?name:confused:

How deep a layer do I need before its compacted? Should I be adding Builders Lime etc to stabilise it or is the compacted gravel itself good enough?

Have done a few searches but havnt come up with much.

Cheers
Joel

[Bodgy]

Again, there are better authorities than I but......

I did exactly this a few years ago, except my drive has a fair slope which made it a little more complex.

Firstly the gravel must be retained, make sure there is at least a 50mm lip around it, up to the final projected level. Its gonna get scattered anyway, but you want to minimise things.

Due to my slope, after spraying for weeds and putting down weedmat, I put in a 75 mm layer of road base. This compacts like concrete and gives the surface gravel something as a key to stop it sliding down the hill.

I chose white, quartz gravel. Luckily I had a mate working for a big quarrying company which kept the price down. The thing to ensure here is that its the right size. I think mine was 15mm screed. Any smaller and it gets stuck in the tread of the cars. Take advice from the quarry who should know this stuff.

Dont put down more than about 50mm. It will slowly compact and become fairly rigid. Any more than 50mm and you'll have trouble getting traction with the tyres.

Hope you don't have teenage boys with cars, they'll do wheelies just to hear the gravel fly.

Good luck

[Trav]

Joel

You certainly need to lay roadbase before the gravel. Then compact it with a plate vibrator. Then add the gravel and vibrate again.

Some people suggest spreading around a bit of concrete to stabilise it all. I've never done it so I can't comment.

Talk to the landscape supplier about the product to use. I would have thought that small stuff will compact harder, but will get in your tyres and wash away easier.

Trav

[DavidG]

JDud
Lay 4" of the yellow/orange decomposed granite from Corkill Bros and water it down.
It sets pretty hard.
Which end of Canberra are you.
I am down deep south and have done my front yard in it.
Come and see if you want. (pm me)

Don't touch the red decomposed granite. It never sets and will wash away.

[la Huerta]

the deco granite it top stuff and unlike gravel it sets hard and firm, with the addition of a few bags of off white cement, but do the prep as above with the road base and it will be almost as good as concrete ...but natural looking...

go to the backyard blitz website , they should have heaps of info on it...

[Bodgy]

Don't wanna be contradictory but I tried adding cement (in an earlier life) to the gravel and it was disastrous. I probably did it incorrectly, but the end result was that the car tyres progressively broke up the 'set' layer of gravel and I ended up with broken 150mm chunks sticking up all over. Looked like the Titanic captain's nightmare.

Not saying it can't work, but maybe research more - it could be tears before bedtime.

[Dan_574]

alot of quarries and other suppliers should have road base / stabalise(Im not sure of the exact name) blended with a set percentage of cement, from around 5% to 15%. I know we can get it here in Melbourne so you should be able to get it up there.

[Bodgy]

Duh............... I'm an idiot, you're talking about adding cement to the roadbase or whatever - NOT the pretty gravel on top.

Got it! Bit slow sometimes, sorry

[JDub]

JDud
Lay 4" of the yellow/orange decomposed granite from Corkill Bros and water it down.
It sets pretty hard.
Which end of Canberra are you.
I am down deep south and have done my front yard in it.
Come and see if you want. (pm me)

Don't touch the red decomposed granite. It never sets and will wash away.

PM sent :)

Definately want the Deco granite style, not the loose gravel.

Thanks for the ideas so far guys.... keep em coming though;)

[jeremy]

Anyone have a recommendation on a good place to purchase the deco granite in Western Suburbs of Sydney??

Cheers,
Jeremy

[inferno6688]

definitly go with road base, say DGB20. compacted well. then the topping. ur local quarry products supplier will no doubt help you out.
Also with you retaining wall make sure it is VERY well drained. That is one of the most common reasons retaining walls fail.

[The Hornet]

Personaly i would go for the extra expense and get some stamped concrete done, we have gravel up at mums, and it is a massive pain in the ****, if its wet, you end up dragging **** in the house, on the floor boards, or nice shiny tiles.

[JDub]

Personaly i would go for the extra expense and get some stamped concrete done, we have gravel up at mums, and it is a massive pain in the ****, if its wet, you end up dragging **** in the house, on the floor boards, or nice shiny tiles.

I did think about that Hornet, but this particular area may, in the future (read 8-10yrs time) be the potential site for a double garage (of unknown dimensions), so I figured it is alot safer to use deco granite ATM and think about concreting if the garage idea ever gets off the ground.

For this same reason I am using one of the block retaining wall systems, so in the future if need be I can disassemble it and relocate it:cool:

Also the water mains (stopcock) is right in the middle of the area :mad: and I am a bit hesitant to concrete around them.

Cheers
Joel

[JDub]

Been doing a bit of research and have come across some conflicting advise (whats new) re: laying of the deco granite:

From the Backyard Blitz website:


Driveway: Nigel upgraded a bare earth driveway into the carport by laying recycled roadbase covered with decomposed granite. The bobcat excavated the loose soil and brought in recycled roadbase. Nigel spread and compacted the roadbase (150mm thick) with a vibrating plate compactor before spreading and compacting gold coloured, decomposed granite (50mm thick) pre-mixed with off-white cement for a stabilising effect. Blitz Tipz For pathways and pedestrian areas a 100mm layer of compacted, decomposed granite, stabilised with off-white cement is sufficient thickness.


From a Landscaping website:



What is decomposed granite used for, and how should it be applied?
Deco Granite is a graded minus 20mm decorative gravel, which can be stabilised and compacted as a hard wearing, decorative driveway or pathway. Deco granite comes in 3 colours, brown, pink and gold, and should be stabilised with cement at 5%, or 1 bag of off-white cement per tonne of Deco Granite for pedestrian use, or 10%, or 2 bags of cement per tonne for driveways. Alternatively Deco Granite can be stabilised with builders lime at 5%, instead of cement.
I have an existing concrete driveway/path, can I lay decomposed granite over the top?
No. Concrete provides a sub-base without flexibility. This may result in the decomposed granite cracking due to expansion and contraction with changes in moisture content and temperature.
How is Deco Granite laid?
Once an appropriate base is established, apply stabilised granite to the required depth (minimum 100mm) then compact with a vibrating 'whacker' plate. If the granite is too dry, puffs of dust will blow out from beneath the whacker. If this happens, lightly water before compacting again.






Thoughts?

One website suggests a thick roadbase with 50mm granite topping.

The other suggests that a minimum of 100mm granite is required and suggests that laying on a hard surface (such as concrete) can cause it to crack down the track.

[JDub]

The latter suggestion of 100mm of granite (omit the roadbase), sounds like the easier option?

Have others that have layed the deco granite used a Road base first?

[kbekus]

Just 2 weeks ago I finished putting in a driveway here at home using Lilydale Toppings which is a crushed granite. I dunno if it's the same stuff as deco granite or not.

Where I live the ground is hard clay, no topsoil, and the bloke who sold the toppings said to lay it straight on the clay, no roadbase needed. So I put down 75mm over 36 square meters and whacked it down. So far it's holding together well and surprisingly little comes inside on my boots.