Driveway foundation Drainage pipes, concrete, footings and foundations. Post your questions and find answers here

[JohnWDIY]

My driveway is old pavia block and I intend to replace it with gravel and increase the area to 81 sq mtrs ie double. This means the old driveway will be compacted sand and the new area is grass.
I intend to put scalpings in as a base layer with a membrane then the top layer of gravel.

Q 1. Do I have to remove the sand?
Q 2. What depth should the scalpings be.
Q 3.What type ie quality and thickness of membrane is required?
Q 4. How deep should the top layer of gravel be?

Thanks.

JohnWDIY.

[ALDA]

JOHN,

A 1. YOU COULD COMBINE/MIX THE SAND WITH THE SCALPINGS TO REDUCE THE QUANTITY OF SCALPINGS REQUIRED AND TO SAVE YOU THE JOB OF REMOVAL/DISPOSAL.

A 2. MINIMUM 4" BUT RECOMMEND 6".
( ALSO DIG OUT LAWN AND TOPSOIL TO FIRM SUB SOIL IN PREPERATION FOR EXTENSION TO DRIVE)

A 3. USE THE BEST YOU CAN AFFORD AS THIS WILL PREVENT PERRENIAL WEEDS FROM COMING UP FOR YEARS TO COME AND AID THE DRAINAGE.

A 4. I WOULD SUGGEST THAT YOU USE AN ANGULAR TYPE GRAVEL AS OPPOSED TO A ROUND TYPE, AS THIS WILL HELP WITH THE ROLLING AND DRIFTING OF THE GRAVEL WHEN THE WHEELS OF THE VEHICLE DRIVE OVER/THROUGH.
THE ANGULAR SECTIONS LOCK/COMPACT BETTER THAN THE ROUND GRAVEL SECTION WHICH TENDS TO ROLL OVER/PAST EACH OTHER.

THICKNESS DEPENDS ON TYPE OF GRAVEL USED BUT IN GENERAL A LAYER OF SOME 3"- 4".

THE BEAUTY OF GRAVEL IS, YOU CAN APPLY LITTLE AND USE DRIVE TO SEE IF IT IS SUFFICIENT AND TOPUP IF REQUIRED.

REGARDS,

ALDA.

[ranec]

I'd like to pull up a tarmac driveway and the lawn next to it and turn it all into a gravel driveway. Total area is 43 square metres.

After lifting the tarmac, what can I expect under it? Can I just compact what I find underneath?

I assume I lift the turf and lose soil, lay and compact scalpings.

Then I lay a membrane over it all and lay my gravel?

TIA

[ALDA]

R,

TARMAC IS OFTEN OVERLAYED ON TOP OF CONCRETE DRIVES/PATHS SO REMOVE SECTION OF TARMAC IN AN INCONSPICUOUS AREA TO VERIFY.

IF IT IS CONCRETED UNDERNEATH, THEN YOU HAVE TO MAKE THE DECISION AS TO WHETHER YOU WANT TO REMOVE THE CONCRETE/TARMAC OR JUST OVERLAY WITH GRAVEL, YOU COULD ALSO OVERLAY IF JUST TARMAC.

THERE ARE NO HARD AND FAST RULES HERE, BUT THE ONE THING TO CHECK IS THAT THE ORIGINAL DRIVE/PATH DRAINS WATER EFFICIENTLY AND THERE IS NO EXCESSIVE PUDDLING.

IF OVERLAYING, THEN THERE WILL BE NO NEED FOR A MEMBRANE BUT THIS SHOULD BE USED WHERE CONVERTING LAWN/GARDEN TO LIMIT REGROWTH OF EXISTING PERENNIAL WEEDS AND NEW WEED GROWTH.

ALSO USE AN ANGULAR GRAVEL AS OPPOSED TO ROUND TYPE IF THE AREA IS TO BE DRIVEN OVER.

ALDA.

[SPOOKS15]

[quote="ALDA"]R,
I TOO HAVE TARMAC UNEVEN DUE TO MATE DROPPING IT OFF CAN I PUT GRAVEL STRAIGHT ON TOP OR SHOULD I BREAK IT UP THEN LAY THE GRAVEL

TARMAC IS OFTEN OVERLAYED ON TOP OF CONCRETE DRIVES/PATHS SO REMOVE SECTION OF TARMAC IN AN INCONSPICUOUS AREA TO VERIFY.

IF IT IS CONCRETED UNDERNEATH, THEN YOU HAVE TO MAKE THE DECISION AS TO WHETHER YOU WANT TO REMOVE THE CONCRETE/TARMAC OR JUST OVERLAY WITH GRAVEL, YOU COULD ALSO OVERLAY IF JUST TARMAC.

THERE ARE NO HARD AND FAST RULES HERE, BUT THE ONE THING TO CHECK IS THAT THE ORIGINAL DRIVE/PATH DRAINS WATER EFFICIENTLY AND THERE IS NO EXCESSIVE PUDDLING.

IF OVERLAYING, THEN THERE WILL BE NO NEED FOR A MEMBRANE BUT THIS SHOULD BE USED WHERE CONVERTING LAWN/GARDEN TO LIMIT REGROWTH OF EXISTING PERENNIAL WEEDS AND NEW WEED GROWTH.

ALSO USE AN ANGULAR GRAVEL AS OPPOSED TO ROUND TYPE IF THE AREA IS TO BE DRIVEN OVER.

ALDA.[/quote]