Driveway sub-base, can I use…
I’ve bought a piece of land at the back of my current garden, which gives me access onto a road at the back. The road is approx 3 feet higher than the garden, so I plan to build a retaining wall which will support a new driveway. The land I have bought is about 150 msq, and is at present covered in those horrible red chips, it would really suit if I could fill up the raised drive area with these things, then I wouldn’t have the hassle of getting rid of them, just moving them instead. There is also a wall to come down which would also provide a fair bit of material for in fill, would it be ok to use all that stuff, then get a compactor plate and bed it down, or would I have to add something like whin or scalpings?
Not sure what to finish with, possibly slabs or Tarmac.
What say the STW experts?Posted 5 years ago
Red chips of what? Colour is not important. 🙂
I assume it’s some sort of single-sized gravel?
For any form of sub-base you need to have some fines in it, or it won’t pack down hard. Type 1 or Scalps is the usual thing, which can either be limestone or more often these days, recycled crushed concrete.
Anything with fines in will pack down virtually rock solid, you cannot lay asphalt straight onto gravel, no.
Re reading your post, if you’re backfilling 3 ft deep, you’re going to need some form of bulk fill, and possibly drainage too. Impossible to say in t’internet really. You might be able to use the chips somewhere in the process, but I wouldn’t backfill 3ft deep with them!Posted 5 years ago
I would have thought you could mix them in somewhere to be fair, then cap off with T1 or scalpings.Posted 5 years ago
Best bet is to call a local independent supplier/haulage firm and explain what you want to do. They’ll know what’s available locally and for what price.
Where do you live, roughly?iaincSubscriber
Greg – your friendly geotechnical engineer to the rescue 😆 as long as it is fairly uniform sized and free draining it will be fine; similarly mix in the stuff from the wall, but try and keep grading (sizing) fairly uniform i.e don’t mix big chuckies and fine gravel. if you have big stuff, blocks etc, get them in at the bottom, with the finer stuff nearer the top. compactor plate during non frozen dryish weather and jobs a good ‘un.
p.s. did Des get any decent pics from the moor ride on Sun ?Posted 5 years agonatrixMember
Before you start, check to see if you’ll need planning permission
Whatever you do, don’t type ‘hardcore’ into google and expect to get advice on your drive!! For all external paving advice check out http://www.pavingexpert.com/home.htmPosted 5 years ago
Cheers Iain, sounds ideal. I’m planning to incorporate some type 1 as well, just to try and bind the whole lot together. I dunno is the big fella got any decent pics, ill text and ask. Can’t make Cathkin on wed night, mrs is working til 8, you fancy Thursday night instead? I could do any time on Thursday after 5.Posted 5 years agoboabymMember
Red chips are just red whin so they will be fine. However once your retaining walls are built I would use the demolished wall first as a bottom layer then if you got hold of a couple of tons of whindust I would mix it with your red chips, this would give you a type of ‘ crush and run’ aggregate. An old cement mixer is good for this i.e. 6 shovels of chips to 1 of dust. Also install your sub base in 4 inch layers and compact with a wacker plate.Posted 5 years ago
Evening.Posted 5 years ago
Pretty much a mix of the above advice, if you use the walling material make sure it’s laid flat and even, possibly use some of the sandy local material to bind in between the bricks/blocks. The top 8 inch of formation wants to be decent stuff. Recycled 6f5 is ok. Quarried 6f5 is great stuff, either can be used for the last six inch then top off with type 1. Always nice to use 50 mm of decent type 1 to top off with as it can be finished off to a decent level pre Tarmac/paving etc. I’d avoid scalpings as they’re not particularly good in wet weather.onewingMember
I would mix the red chips in with some type 1 crushed bricks concrete etc. Then compact with a whacker plate. Depending on the depth on the level you are making up, you may need to lay part of the type 1. compact it , then lay some more, then compact it. And repeat till you get your finished level.Posted 5 years ago
This makes sure all the voids are removed and you get a nice solid base.
It’s just bigger sized aggregate, recycled being old bricks concrete etc put thro a crusher, usually nothing bigger than 70mm sometimes a ball ache as you’ll get nails/ bits of mesh in it, which isn’t ideal if you want to use it pre surfacing. Quarried being the recycled stuff but from virgin material so no crap in it. Probably £4/tonne cheaper on a 20t load.Posted 5 years agotimberMember
Depends on the stone in your local quarry too (from my experience of building forestry tracks) We mostly use crush and run, where this comes from a sandstone quarry, it packs to a smooth polish just through driving over it. The limestone stuff we have to top with scalpings if we need a smooth finish for public access (footpath/disabled access).Posted 5 years ago
The limestone stuff gives better drainage and traction we find, but our tracks do go through muddy holes.Baron_von_draisMember
6f5 is a specific graded crush fine, 6f2 would be a course version.
The grading for 6F5 and 6F2 are identical and for the OP purposes are the same thing. 6F5 is material specifically imported to a site, 6F2 can be “site won”.
The grading is quite wide and can range from 125mm to “dust” in varying percentages. Don’t try to lay surfacing straight on to that if you want a decent finish that will last. The material that others have referred to as crush and run (or crusher run) is effectively the same thing.
As wrightyson says, ideally it should be topped with 50-75mm of MOT Type 1 if you want a good finish laid to a fall that you can then lay surfacing on.Posted 5 years ago
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