Posted: Fri May 19, 2006 10:33 am
I recently re-graveled the front drive of my house. I did the job in a hurry to meet other deadlines and now have to deal with some problems.
The original surface was gravel which over time had become mixed with the underlying clay/ falling leaves to the extent that it resembled a kind of muddy concrete. Beneath this was a layer of hardcore which was clinker from the small-scale industrial forges which were a feature of the area 100 years ago. I decided not to rip it all out and replace it, but simply to improve the drainage and top up the gravel. But I did make a decision to do more than just add fresh gravel, and thought I would try using modern membrane materials. It's the correct use of those membranes that's the issue here, and the point of my question.
I installed drainage in the form of a bottle gulley to an existing RW drain, supplemented by a run of clay land-drain into the gulley.
I removed loose pebbles and debris from the compacted clay and gravel surface and laid down 2metre-wide (7') strips of black weed-guard fabric. I secured the joins with galvanised steel banding fixed in place by 6" (150mm) nails into the substrate. On top of this, I laid 2" (50mm) of 20mm gravel.
The end result is OK. It's like walking over a shingle beach. The noise gives good intruder warning and it has put an end to all former drainage problems. However, there is a downside.
Driving across it in a 4-wheel drive road vehicle is fine, but a 2-wheel drive going across it is a little bit difficult and can get slightly bogged down. Only a minor inconvenience, but noticeable. But when a truck came to tip some more gravel, when it tried to move off when empty, its wheels spun, ripping up the weed-guard fabric.
The company that supplied the gravel suggested I put hardcore underneath it. However, I'm not convinced by this suggestion as the substrate is firm and hard already, and hardcore would substantially raise the ground-level. The purpose of hardcore is mainly as a foundation and the existing hardcore foundation beneath the old gravel is fine from that point of view.
I think that a 1/2" (12mm) layer of either sharp sand or pea-shingle laid directly onto the weed-guard fabric, with a reduced thickness of the 20mm gravel – say an inch or so, might well work.
I considered nailing ACO ground-guard to the fabric as an alternative, but this has two disadvantages. First, it is expensive and second, it would prevent raking of the gravel apart from the very top layer. Raking is important to assist debris to find their way through the gravel.
Would a layer of sharp sand laid on top of the weed-guard but beneath the gravel help it to bed in and protect the fabric from wheel damage..? Has anyone ever done this..?
Thanks,
Andy Morley
The original surface was gravel which over time had become mixed with the underlying clay/ falling leaves to the extent that it resembled a kind of muddy concrete. Beneath this was a layer of hardcore which was clinker from the small-scale industrial forges which were a feature of the area 100 years ago. I decided not to rip it all out and replace it, but simply to improve the drainage and top up the gravel. But I did make a decision to do more than just add fresh gravel, and thought I would try using modern membrane materials. It's the correct use of those membranes that's the issue here, and the point of my question.
I installed drainage in the form of a bottle gulley to an existing RW drain, supplemented by a run of clay land-drain into the gulley.
I removed loose pebbles and debris from the compacted clay and gravel surface and laid down 2metre-wide (7') strips of black weed-guard fabric. I secured the joins with galvanised steel banding fixed in place by 6" (150mm) nails into the substrate. On top of this, I laid 2" (50mm) of 20mm gravel.
The end result is OK. It's like walking over a shingle beach. The noise gives good intruder warning and it has put an end to all former drainage problems. However, there is a downside.
Driving across it in a 4-wheel drive road vehicle is fine, but a 2-wheel drive going across it is a little bit difficult and can get slightly bogged down. Only a minor inconvenience, but noticeable. But when a truck came to tip some more gravel, when it tried to move off when empty, its wheels spun, ripping up the weed-guard fabric.
The company that supplied the gravel suggested I put hardcore underneath it. However, I'm not convinced by this suggestion as the substrate is firm and hard already, and hardcore would substantially raise the ground-level. The purpose of hardcore is mainly as a foundation and the existing hardcore foundation beneath the old gravel is fine from that point of view.
I think that a 1/2" (12mm) layer of either sharp sand or pea-shingle laid directly onto the weed-guard fabric, with a reduced thickness of the 20mm gravel – say an inch or so, might well work.
I considered nailing ACO ground-guard to the fabric as an alternative, but this has two disadvantages. First, it is expensive and second, it would prevent raking of the gravel apart from the very top layer. Raking is important to assist debris to find their way through the gravel.
Would a layer of sharp sand laid on top of the weed-guard but beneath the gravel help it to bed in and protect the fabric from wheel damage..? Has anyone ever done this..?
Thanks,
Andy Morley
