Re-using block paving - Need to re use my paving

[Mick Leek]

Hi Tony,

You have helped me in the other areas of my current project and i know you will definatly be able to help me with this one.

As you are aware, i am in the middle of building an extension. One of the critera of the planning was that i provide off street parking for 2 cars.

Whilst digging out the footings we had to lift quite a large area of our Clay Paved driveway. One thing i had noticed was that the area submitted to the most use ( where the car runs on and off the drive ) Had sunk slightly. maybe an inch or so but certainly noticable. although the guys who originally layed it where road workers for the local council, They used what i was told was BLACK limestone ?. It is quite course stuff although there seems to be a lot of smaller gravel and dust within the mix. There is approx 4" of this and below that a couple of inches of crush a run, and below that it is clay. The sand bed seems non exsistant maybe half an inch in places.

My question is " Is there really a black limestone, and if it sounds dodgy to you, will i have to lift it all and get a decent sub base like crush a run" ?

I want to lift the entire drive and re lay all of it once the extension is complete but would like to make sure i dont get a re occurance of the settlement where the car runs the most.

Thanks,

Mick.

[Tony McC]

Black limestone is a reality, but it's not found everywhere. Much of it comes from N.Wales although some has been imported from Norway in the past.

You're unlikely to improve on what you have for a sub-base. You might need to re-grade it to get the correct levels, and those salvaged clay pavers will need to be re-laid on 30-40mm of grit sand, but from what you've told me, there's nowt to be gained in digging out the sub-base.

[Mick Leek]

Thanks Tony,

I do recall that they didnt seem to give it much action with the vibrating plate.

They gave it a couple of passes then layed the sand and paving finally spreading sand over the surface and gave it a few more passes.

Does it sound as if it needs a little more action on the sub before the final 40mm of grit sand ?

Thanks,

Mick

[Tony McC]

It can't do it any harm!